Alpinestars A-4 Plasma Roost Guard Adult Off-Road Body Armor
- Anatomically profiled for all forms of off-road riding
 - Features a semi-rigid thermoplastic polyhedron design chest protector and a Nucleon Plasma back protector that are engineered to be lightweight, breathable, comfortable, adaptive, and protective
 - Highly flexible Nucleon Plasma Back Protector constructed from viscoelastic material engineered from biobased polymers and formed into a structure that is pliable in all directions while maintaining the ability to dissipate impact energies
 - Lightweight and highly ventilated, this protector offers strong impact force dispersion and absorption while ensuring maximum coverage areas in all riding positions
 - Lightweight and ultra-vented chest armor
 - The chest outer shell’s design achieves the desired structural strength and imposed load performance when compared to flat or unfaceted surfaces
 - The over-injected flexible side wings of the chest protector follows the body's contours for comfort and freedom of movement
 - Optional Race Kit — Engineered to be compatible with the Nucleon Plasma Extended Roost Coverage kit which includes Upper and Lower Chest Extensions, and an additional Y-Strap System to use the A-4 Chest without the back protector
 - Features highly perforated, adjustable, and detachable rib and shoulder padding for additional rib and shoulder coverage against roost and impact
 - Equipped with adjustable shoulder and side straps for an optimized performance fit
 - Removable soft tactile thermoformed shoulder padding for enhanced rider comfort
 - The lining on the back protector offers a soft tactile feeling against the skin while maintaining the integral structure of the protectors and reducing the risk of any material tearing
 - The lining is ribbed for superior airflow while also reducing the amount of material that is in contact with the skin
 - The perforated 3D mesh chassis also offers additional protection against tire roost
 - Bionic Neck Support compatibility via the BNS shoulder pull tabs
 - USDA certified bio-based eco-friendly and sustainable impact absorbing material
 - Colors: Black / Red / White
 - Sizes: Medium / Large, X-Large / 2X-Large
 - SKU: 2701-1507, 2701-1508
 


New or Brand New - Brand new item in original packaging (original manufacturer's warranty may apply).
Refurbished - Professionally restored and in perfect working condition. Original packaging may be missing or slightly damaged.
Used - Item has seen limited use but remains in good working condition. May show some limited signs of wear with small scratches or cosmetic blemishes. May arrive with damaged packaging or be repackaged.
Refurbished, Without Tags - Same as refurbished. Item may arrive with mising labels or tags.
Refurbished, Last Call - Same as refurbished. Last call or closeout item.
HOW TO MEASURE
A | CHEST
Measure around the fullest part, under the armpits, keeping the tape horizontal.
B | WAIST
Measure around the natural waist line, inline with the navel, keeping the tape horizontal.
C | HIP
Measure around the fullest part of your hips, about 20cm below waist line, keeping the tape horizontal.
D | THIGH
Measure around the thigh just below the crotch, keeping the tape horizontal.
E | INSEAM
Stand against a wall, ask someone else to measure from the crotch to the bottom of your leg.
F | ARM LENGTH
Measure from shoulder (Humerus) to wrist.
G | HEIGHT
Stand against a wall, ask someone else to measure from the oor to the top of your head, keeping the tape vertical.
MEN'S APPAREL SIZE CHART (INCHES)
| Euro Size | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 54 | 56 | 58 | 60 | 62 | 64 | 
| International Size | XXS | XXS | XS | XS | S | S | S | M | M | L | L | XL | L | XL | XL | XXL | XXL | XXL | 3XL | 3XL | 4XL | 
| U.S. Size | 30 | 32 | 34 | 36 | 38 | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 54 | 
| U.S. Pant Size | 24 | 26 | 28 | 30 | 32 | 34 | 36 | 38 | 40 | 42 | 44 | 46 | 48 | 
| A | Chest (Inches) | 30 3/4- 32 1/4 | 32 1/4- 33 7/8 | 33 7/8- 35 3/8 | 35 3/8- 37 | 37 - 38 5/8 | 38 5/8- 40 1/8 | 40 1/8- 41 3/4 | 41 3/4- 43 1/4 | 43 1/4- 44 7/8 | 44 7/8- 46 1/2 | 46 1/2- 48 | 48 - 49 5/8 | 49 5/8- 51 1/8 | 
| B | Waist (Inches) | 25 1/4- 26 3/4 | 26 3/4- 28 3/8 | 28 3/8- 29 7/8 | 29 7/8- 31 1/2 | 31 1/2- 33 1/8 | 33 1/8- 34 5/8 | 34 5/8- 36 1/4 | 36 1/4- 37 3/4 | 37 3/4- 39 1/4 | 39 1/4- 41 | 41 - 42 1/2 | 42 1/2- 44 1/8 | 44 1/8- 45 5/8 | 
| C | Hip (Inches) | 31 1/8- 32 5/8 | 32 5/8- 34 1/4 | 34 1/4- 35 7/8 | 35 7/8- 37 3/8 | 37 3/8- 39 | 39 - 40 1/2 | 40 1/2- 42 1/8 | 42 1/8- 43 3/4 | 43 3/4- 45 1/4 | 45 1/4- 46 7/8 | 46 7/8- 48 3/8 | 48 3/8- 50 | 50 - 51 5/8 | 
| D | Thigh (Inches) | 19 3/8- 19 5/8 | 19 5/8- 20 1/8 | 20 1/2- 20 7/8 | 21 1/4- 21 5/8 | 22 - 22 1/2 | 22 7/8- 23 1/4 | 23 5/8- 24 | 24 3/8- 24 3/4 | 25 1/4- 25 5/8 | 26 - 26 3/8 | 26 3/4- 27 1/8 | 27 1/2- 28 | 28 3/8- 28 1/2 | 
| E | Inseam (Inches) | 28 - 28 3/4 | 28 3/4- 29 1/8 | 29 1/2- 29 7/8 | 30 3/8- 30 3/4 | 31 1/8- 31 1/2 | 31 7/8 - 32 1/4 | 32 5/8 - 33 1/8 | 33 1/2 - 33 7/8 | 34 1/4 - 34 5/8 | 35 - 35 3/8 | 35 - 35 3/8 | 35 7/8 - 36 1/4 | 35 7/8 - 36 1/4 | 
| F | Outer Arm (Inches) | 19 1/4 - 20 1/8 | 20 1/8 - 20 3/4 | 20 7/8 - 21 1/4 | 21 5/8 - 22 | 22 1/2 - 22 7/8 | 23 1/4 - 23 5/8 | 24 - 24 3/8 | 24 3/4 - 25 1/4 | 25 5/8 - 26 | 26 3/8 - 26 3/4 | 26 3/8 - 26 3/4 | 27 1/8 - 27 1/2 | 27 1/8 - 27 1/2 | 
| G | Height (Inches) | 4'11" - 5'1" | 5'2" - 5'4" | 5'4" - 5'5 | 5'6" - 5'7" | 5'7" - 5'8" | 5'9" - 5'10" | 5'11" - 6'" | 6" - 6'2" | 6'2" - 6'3" | 6'3" - 6'5" | 6'3" - 6'5" | 6'5" - 6'6" | 6'5" - 6'6" | 
MEN'S APPAREL SIZE CHART (CM)
| Euro Size | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 54 | 56 | 58 | 60 | 62 | 64 | 
| International Size | XXS | XXS | XS | XS | S | S | S | M | M | L | L | XL | L | XL | XL | XXL | XXL | XXL | 3XL | 3XL | 4XL | 
| U.S. Size | 30 | 32 | 34 | 36 | 38 | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 54 | 
| U.S. Pant Size | 24 | 26 | 28 | 30 | 32 | 34 | 36 | 38 | 40 | 42 | 44 | 46 | 48 | 
| A. Chest (cm) | 78 - 82 | 82 - 86 | 86 - 90 | 90 - 94 | 94 - 98 | 98 - 102 | 102 - 106 | 106 - 110 | 110 - 114 | 114 - 118 | 118 - 122 | 122 - 126 | 126 - 130 | 
| B. Waist (cm) | 64 - 68 | 68 - 72 | 72 - 76 | 76 - 80 | 80 - 84 | 84 - 88 | 88 - 92 | 92 - 96 | 96 - 100 | 100 - 104 | 104 - 108 | 108 - 112 | 112 - 116 | 
| C. Hip (cm) | 79 - 83 | 83 - 87 | 87 -91 | 91 - 95 | 95 - 99 | 99 - 103 | 103 - 107 | 107 - 111 | 111 - 115 | 115 - 119 | 119 - 123 | 123 - 127 | 127 - 131 | 
| D. Thigh (cm) | 48 - 49 | 50 - 51 | 52 - 53 | 54 - 55 | 56 - 57 | 58 - 59 | 60 - 61 | 62 - 63 | 64 - 65 | 66 - 67 | 68 - 69 | 70 - 71 | 72 - 73 | 
| E. Inseam (cm) | 71 - 72 | 73 - 74 | 75 - 76 | 77 - 78 | 79 - 80 | 81 - 82 | 83 - 84 | 85 -86 | 87 - 88 | 89 - 90 | 89 - 90 | 91 - 92 | 91 - 92 | 
| F. Outer Arm (cm) | 49 - 50 | 51 - 52 | 53 - 54 | 55 - 56 | 57 - 58 | 59 - 60 | 61 - 62 | 63 - 64 | 65 - 66 | 67 - 68 | 67 - 68 | 69 - 70 | 69 - 70 | 
| G. Height (cm) | 150 - 156 | 157 - 163 | 164 - 167 | 168 - 171 | 172 - 175 | 176 - 179 | 180 - 183 | 184 - 187 | 188 - 191 | 192 - 195 | 192 - 195 | 196 - 199 | 196 - 199 | 
| Europe | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 
| USA | 3.5 | 4 | 5 | 6 | 6.5 | 7.5 | 8 | 9 | 9.5 | 10.5 | 11.5 | 12 | 12.5 | 13.5 | 14 | 
| Japan | 22.5 | 23 | 24 | 25 | 25.5 | 26 | 26.5 | 27.5 | 28.5 | 29.5 | 30 | 30.5 | 31.5 | 32 | 33 | 

A | CHEST
Measure around the chest under the armpits, keeping the tape horizontal.
B | BUST
Measure around the fullest part of the bust, keeping the tape horizontal.
C | WAIST
Measure around the natural waist line, inline with the navel, keeping the tape horizontal.
D | HIP
Measure around the fullest part of your hips, about 20cm below waist line, keeping the tape horizontal.
E | THIGH
Measure around the thigh just below the crotch, keeping the tape horizontal.
F | INSEAM
Stand against a wall, ask someone else to measure from the crotch to the bottom of your leg.
G | ARM LENGTH
Measure from shoulder (Humerus) to wrist.
H | HEIGHT
Stand against a wall, ask someone else to measure from the floor to the top of your head, keeping the tape vertical.
| Euro Size | 36 | 38 | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 54 | 
| International Size | XXS | XXS | XS | XS | S | M | L | L | XL | XL | XXL | XXL | XXL | 3XL | 3XL | 
| U.S. Size | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 
| U.S. Pant Size | 22 | 24 | 26 | 28 | 30 | 32 | 34 | 36 | 38 | 40 | 
| A. Chest (Inches) | 29 1/8 - 30 3/4 | 30 3/4 - 32 1/4 | 32 1/4 - 33 7/8 | 33 7/8 - 35 3/8 | 35 3/8 - 37 | 37 - 38 5/8 | 38 5/8 - 40 1/8 | 40 1/8 - 41 3/4 | 41 3/4 - 43 1/4 | 43 1/4 - 44 7/8 | 
| B. Bust (Inches) | 30 3/4 - 32 1/4 | 32 1/4 - 33 7/8 | 33 7/8 - 35 3/8 | 35 3/8 - 37 | 37 - 38 5/8 | 38 5/8 - 40 1/8 | 40 1/8 - 41 3/4 | 41 3/4 - 43 1/4 | 43 1/4 - 44 7/8 | 44 7/8 - 46 1/2 | 
| C. Waist (Inches) | 22 7/8 - 24 3/8 | 24 3/8 - 26 | 26 - 27 1/2 | 27 1/2 - 29 1/8 | 29 1/8 - 30 3/4 | 30 3/4 - 32 1/4 | 32 1/4 - 33 7/8 | 33 7/8 - 35 3/8 | 35 3/8 - 37 | 37 - 38 5/8 | 
| D. Hip (Inches) | 32 1/4 - 33 7/8 | 33 7/8 - 35 3/8 | 35 3/8 - 37 | 37 - 38 5/8 | 38 5/8 - 40 1/8 | 40 1/8 - 41 3/4 | 41 3/4 - 43 1/4 | 43 1/4 - 44 7/8 | 44 7/8 - 46 1/2 | 46 1/2 - 48 | 
| E. Thighs (Inches) | 19 5/8 - 20 1/8 | 20 1/2 - 20 7/8 | 21 1/4 - 21 5/8 | 22 - 22 1/2 | 22 7/8 - 23 1/4 | 23 5/8 - 24 | 24 3/8 - 24 3/4 | 25 1/4 - 25 5/8 | 26 - 26 3/8 | 26 3/4 - 27 1/8 | 
| F. Inner Legs (Inches) | 28 3/8 - 28 3/4 | 29 1/8 - 29 1/2 | 29 7/8 - 30 3/8 | 30 3/4 - 31 1/8 | 31 1/2 - 31 7/8 | 32 1/4 - 32 5/8 | 33 1/8 - 33 1/2 | 33 1/8 - 33 1/2 | 33 7/8 - 34 1/4 | 33 7/8 - 34 1/4 | 
| G. Outer Legs (Inches) | 19 5/8 - 20 1/8 | 20 1/2 - 20 7/8 | 21 1/4 - 21 5/8 | 22 - 22 1/2 | 22 7/8 - 23 1/4 | 23 5/8 - 24 | 24 3/8 - 24 3/4 | 24 3/8 - 24 3/4 | 25 1/4 - 25 5/8 | 25 1/4 - 25 5/8 | 
| H. Height (Inches) | 5'2"- 5'3" | 5'4"- 5'5" | 5'5"- 5'6" | 5'7"- 5'8" | 5'8"- 5'9" | 5'10"- 5'11" | 5'11"- 6'" | 5'11"- 6'" | 6'1"- 6'2" | 6'1"- 6'2" | 

| Europe | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 
| USA | 5 | 6 | 7 | 8 | 8.5 | 9 | 10 | 11 | 11.5 | 
| Japan | 22.5 | 23 | 24 | 25 | 25.5 | 26 | 26.5 | 27.5 | 28 | 

| Measurement | Letter Sizing | Numeric Sizing | 
|---|---|---|
| 2 1/8" - 2 5/8" | XS | 7 | 
| 2 5/8" - 3 1/8" | SM | 8 | 
| 3 1/8" - 3 5/8" | MD | 9 | 
| 3 5/8" - 4 1/8" | LG | 10 | 
| 4 1/8" - 4 5/8" | XL | 11 | 
| 4 5/8" - 5 1/8" | XXL | 12 | 
| 5 1/8" - 5 5/8" | XXXL | 13 | 

Off-Road Boots
| US | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 
| EU | 38 | 39 | 40.5 | 42 | 43 | 44.5 | 45.5 | 47 | 48 | 49.5 | 51 | 52 | 
Road Boots
| US | 3.5 | 4 | 5 | 6 | 6.5 | 7.5 | 8 | 9 | 9.5 | 10.5 | 11.5 | 12 | 12.5 | 13.5 | 14 | 
| EU | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 
Leather Jacket
| Size | A| Chest | B| Waist | C| Hip | D| Height | ||||
|---|---|---|---|---|---|---|---|---|
| Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | |
| 46 | 36 1/4 in | 92 cm | 29 7/8 in | 76 cm | 36 1/4 in | 92 cm | 5' 9" | 174 cm | 
| 48 | 37 3/4 in | 96 cm | 31 1/2 in | 80 cm | 37 3/4 in | 96 cm | 5'10" | 177 cm | 
| 50 | 39 3/8 in | 100 cm | 33 1/8 in | 84 cm | 39 3/8 in | 100 cm | 5' 11" | 180 cm | 
| 52 | 41 in | 104 cm | 34 5/8 in | 88 cm | 41 in | 104 cm | 6' | 183 cm | 
| 54 | 42 1/2 in | 108 cm | 36 1/4 in | 92 cm | 42 1/2 in | 108 cm | 6' 1" | 186 cm | 
| 56 | 44 1/8 in | 112 cm | 37 3/4 in | 96 cm | 44 1/8 in | 112 cm | 6' 3" | 189 cm | 
| 58 | 45 5/8 in | 116 cm | 39 3/8 in | 100 cm | 45 5/8 in | 116 cm | 6' 4" | 192 cm | 
| 60 | 47 1/4 in | 120 cm | 41 in | 104 cm | 47 1/4 in | 120 cm | 6' 5" | 195 cm | 
| 62 | 48 3/4 in | 124 cm | 42 1/2 in | 108 cm | 48 3/4 in | 124 cm | 6' 6" | 198 cm | 
| 64 | 50 1/4 in | 128 cm | 44 in | 112 cm | 50 1/4 in | 128 cm | 6' 6" | 198 cm | 

Leather Suit Jacket
| Size | A| Chest | B| Waist | C| Hip | D| Inseam | E| Height | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| US | EU | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | 
| 36 | 46 | 36 1/4 in | 92 cm | 29 7/8 in | 76 cm | 36 1/4 in | 92 cm | 30 in | 76.2 cm | 5' 9" | 174 cm | 
| 38 | 48 | 37 3/4 in | 96 cm | 31 1/2 in | 80 cm | 37 3/4 in | 96 cm | 32 in | 81.3 cm | 5'10" | 177 cm | 
| 40 | 50 | 39 3/8 in | 100 cm | 33 1/8 in | 84 cm | 39 3/8 in | 100 cm | 34 in | 86.4 cm | 5' 11" | 180 cm | 
| 42 | 52 | 41 in | 104 cm | 34 5/8 in | 88 cm | 41 in | 104 cm | 34 in | 86.4 cm | 6' | 183 cm | 
| 44 | 54 | 42 1/2 in | 108 cm | 36 1/4 in | 92 cm | 42 1/2 in | 108 cm | 36 in | 91.4 cm | 6' 1" | 186 cm | 
| 46 | 56 | 44 1/8 in | 112 cm | 37 3/4 in | 96 cm | 44 1/8 in | 112 cm | 36 in | 91.4 cm | 6' 3" | 189 cm | 
| 48 | 58 | 45 5/8 in | 116 cm | 39 3/8 in | 100 cm | 45 5/8 in | 116 cm | 38 in | 96.5 cm | 6' 4" | 192 cm | 
| 50 | 60 | 47 1/4 in | 120 cm | 41 in | 104 cm | 47 1/4 in | 120 cm | 38 in | 96.5 cm | 6' 5" | 195 cm | 
| - | 62 | 48 3/4 in | 124 cm | 42 1/2 in | 108 cm | 48 3/4 in | 124 cm | 40 in | 101.5 cm | 6' 6" | 198 cm | 
| - | 64 | 50 1/4 in | 128 cm | 44 in | 112 cm | 50 1/4 in | 128 cm | 40 in | 101.5 cm | 6' 6" | 198 cm | 

| Measurement | Letter Sizing | Numeric Sizing | 
|---|---|---|
| 2 1/8" - 2 5/8" | XS | 7 | 
| 2 5/8" - 3 1/8" | SM | 8 | 
| 3 1/8" - 3 5/8" | MD | 9 | 
| 3 5/8" - 4 1/8" | LG | 10 | 
| 4 1/8" - 4 5/8" | XL | 11 | 
| 4 5/8" - 5 1/8" | XXL | 12 | 
| 5 1/8" - 5 5/8" | XXXL | 13 | 

Off-Road Boots
| US | 6 | 7 | 8 | 9 | 10 | 
| EU | 37 | 38 | 39 | 41 | 42 | 
Road Boots
| US | 5.5 | 6 | 7 | 8 | 8.5 | 9.5 | 10 | 11 | 
| EU | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 
Leather Jackets
| Size | A| Bust | B| Waist | C| Hip | D| Height | |||||
|---|---|---|---|---|---|---|---|---|---|
| US | EU | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | 
| 0 | 36 | 31 1/2 in | 80 cm | 23 1/2 in | 60 cm | 33 in | 84 cm | 5' 3" | 160 cm | 
| 2 | 38 | 33 in | 84 cm | 25 1/4 in | 64 cm | 34 3/4 in | 88 cm | 5' 4" | 163 cm | 
| 4 | 40 | 34 3/4 in | 88 cm | 26 3/4 in | 68 cm | 36 1/4 in | 92 cm | 5' 5" | 166 cm | 
| 6 | 42 | 36 1/4 in | 92 cm | 28 1/4 in | 72 cm | 37 3/4 in | 96 cm | 5' 7" | 169 cm | 
| 8 | 44 | 37 3/4 in | 96 cm | 30 in | 76 cm | 39 1/4 in | 100 cm | 5' 8" | 172 cm | 
| 10 | 46 | 39 1/4 in | 100 cm | 31 1/2 in | 80 cm | 41 in | 104 cm | 5' 9" | 175 cm | 
| 12 | 48 | 41 in | 104 cm | 33 1/4 in | 84 cm | 42 1/2 in | 108 cm | 5' 10" | 178 cm | 
| 14 | 50 | 41 1/2 in | 108 cm | 34 3/5 in | 88 cm | 44 in | 112 cm | 5' 11" | 181 cm | 

Leather Suit
| Size | A| Bust | B| Waist | C| Hip | D| Inseam | E| Height | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| US | EU | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | Inches | Centimeters | 
| 0 | 36 | 31 1/2 | 80 cm | 23 1/2 | 60 cm | 33 | 84 cm | 30 1/4 | 77 cm | 5' 3" | 160 cm | 
| 2 | 38 | 33 in | 84 cm | 25 1/4 in | 64 cm | 34 3/4 in | 88 cm | 31 in | 79 cm | 5' 4" | 163 cm | 
| 4 | 40 | 34 3/4 in | 88 cm | 26 3/4 in | 68 cm | 36 1/4 in | 92 cm | 31 in | 79 cm | 5' 5" | 166 cm | 
| 6 | 42 | 36 1/4 in | 92 cm | 28 1/4 in | 72 cm | 37 3/4 in | 96 cm | 32 in | 81 cm | 5' 7" | 169 cm | 
| 8 | 44 | 37 3/4 in | 96 cm | 30 in | 76 cm | 39 1/4 in | 100 cm | 32 in | 81 cm | 5' 8" | 172 cm | 
| 10 | 46 | 39 1/4 in | 100 cm | 31 1/2 in | 80 cm | 41 in | 104 cm | 32 3/4 in | 83 cm | 5' 9" | 175 cm | 
| 12 | 48 | 41 in | 104 cm | 33 1/4 in | 84 cm | 42 1/2 in | 108 cm | 33 1/2 in | 85 cm | 5' 10" | 178 cm | 
| 14 | 50 | 41 1/2 in | 108 cm | 34 3/5 in | 88 cm | 44 in | 112 cm | 34 1/4 in | 87 cm | 5' 11" | 181 cm | 
*  Sizing information is provided by the manufacturer and does not guarantee a perfect fit. 
