Alpinestars Bionic Plasma Knee Protector Youth Off-Road Body Armor
Built for motocross and off-road riding, the Bionic Plasma Youth Knee Protector combines flexible Nucleon PLASMA impact protection with a ventilated chassis to help young riders stay comfortable and move naturally on the bike.
- Highly Comfortable: The Nucleon PLASMA knee protector is made from a viscoelastic material that absorbs and disperses impact energy while providing maximum coverage in all riding positions. Engineered for multi-directional pliability, the protector conforms to the knee for a snug and secure fit, and delivers reliable protection
- Ventilated Chassis Design: The chassis features a 3D mesh front panel for superior levels of ventilation and airflow, along with abrasion-resistant fabric that covers the knee area
- Stretch Mesh, Ventilated Construction: Soft, stretch mesh at the rear of the lower legs provides a comfortable fit for riders with various calf sizes, while the open knee construction behind the knee helps to prevent heat build-up while maximizes ventilation
- Extended Coverage: Extra side padding for extended coverage
- Nucleon PLASMA Knee Protector (EN 1621-1:2012) - CE Level 1
- The Nucleon PLASMA element is constructed from a bio-based viscoelastic impact-absorbing compound containing no less than 25% Bio-based content and molded into a precision-engineered geometry. The PLASMA material dissipates impact energy and significantly reduces transmitted forces through controlled material response. Its low-profile geometry is specifically developed to compress and extend with movement, while its channeled, highly perforated design supports airflow
- Extra side padding provides extended coverage
- The Level 1 CE-certified Nucleon PLASMA knee protector is removable for easy cleaning
- Soft tactile inner padding enhances rider comfort
- The pre-shaped construction features soft-touch, perforated stretchable padding for enhanced comfort and superior airflow
- The anatomically sculpted upper calf and upper hem silicon strips keep the protector securely in position
- Colors: Black / White
- Sizes: Small/Medium, Large/X-Large, 2X-Large
- SKU: 2704-0814, 2704-0815, 2704-0816



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.
