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USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Aug 15 - Aug 20
For Your Every Summer RSVP, with Code: SUMMER15
Description
ALPINESTARS A-4 PLASMA ROOST GUARDFeatures 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 Key Features 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
Features
- 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
- Key Features
- 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
- Construction
- 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
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.2 ★★★★★
Based on 12 reviews
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Product Reviews
★★★★★ 3
Too loose
Size: Large, Color: Brown
The size ran too big/loose. For example, it you tend to wear Large, order a Medium for this instead.
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Reviewed in the United States on May 8, 2026
★★★★★ 5
great value
Size: Small, Color: Dark Blue
excellent
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Reviewed in the United States on February 14, 2026
★★★★★ 1
Construction is quite inferior and it stays badly wrinkled
Size: X-Large, Color: Dark Blue
Inferior construction. The mock turtle neck did not stay up but folded over.
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Reviewed in the United States on May 4, 2026
★★★★★ 5
Mock shirt for everyday wear.
Color: Gray Green, Lotus Pink, Sky Blue, Size: X-Large
Love how soft the fabric is and wears very well. Very happy with purchase and have bought other colors as well.
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Reviewed in the United States on May 22, 2026
★★★★★ 3
Amazon brand looks bad
Color: White, Light Gray, Black, Size: X-Large
II think the quality is poor the fabric is thin and the moc collar won't stand up
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Reviewed in the United States on July 20, 2025