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1. CE Level 2 certification (EN 1621-3:2018 Level 2) for chest protection at £49.99 represents excellent value for the highest protection tier — Level 2 chest protection at this price is uncommon
2. Nucleon Cell microstructure designed for advanced energy absorption, adaptivity, and maximum breathability — the cellular architecture distributes impact forces laterally across the cell network rather than transmitting them to the chest
3. Airmesh body contact surface provides maximum breathability from the protector face against the rider’s chest, keeping the chest cooler during track use than solid-backed protectors
1. Chest-only protector covering the chest impact zone; riders who also want back protection will need the Nucleon Kr-Celli or similar back insert alongside this product
2. Ergonomic back plate design contours to the natural curve of the back, suggesting this is designed as a front-mounting protector within a suit or separate vest — riders should confirm fitment compatibility with their suit or jacket
3. The product name references KR (Karting/Racing) and CiR (Chest inner Rider), suggesting this is specifically designed for the riding suit environment rather than general jacket use
Track and circuit riding creates specific chest protection requirements that differ from off-road applications: the priority is lightweight, low-profile protection that can be worn for extended sessions in a leather suit without creating comfort issues, with impact performance matched to the crash dynamics of circuit racing rather than MX. The Alpinestars Nucleon KR-Cell CiR Chest Protectors are designed specifically for this environment, delivering CE Level 2 certification through the Nucleon Cell technology architecture in a construction focused on breathability and performance fit.
The chest shell uses a double-layered construction based on the Nucleon Cell microstructure: a high-performance polymeric material blend where the structure is a Cell architecture rather than a solid panel. The Cell microstructure changes from the centre of the protector towards the outside, varying the density and flexibility of the cellular geometry to match the energy absorption required at each zone. The centre of the protector, which takes the highest direct impact loads, uses a denser Cell structure for maximum energy absorption; the outer zones use a more flexible Cell structure that accommodates the natural chest curvature and body movement.
This graduated Cell approach provides the perfect balance between force dispersion and energy absorption across the full protector face, with CE Level 2 certification confirming the system meets the most demanding formally specified standard for chest protection. The protector is ergonomically contoured to the natural curve of the chest for optimum fit during riding, rather than presenting a flat panel that creates pressure points.
The body contact face of the protector uses a soft comfortable airmesh material that provides maximum breathability and rider comfort against the chest. Track use typically involves higher sustained body temperatures than road riding, and the airmesh face prevents the heat accumulation that solid-backed protectors create during sustained wearing.
The Nucleon KR-Cell CiR Protectors are for circuit and track riders who use leather suits and want CE Level 2 chest protection in a lightweight, breathable format specifically designed for the track riding environment. The Nucleon Cell technology, graduated cellular architecture, and airmesh body contact face make these appropriate for riders who want serious chest protection certification without the bulk or weight of motorcycle jacket chest inserts.
– CE Level 2: EN 1621-3:2018 Level 2
– Double-layered Nucleon Cell microstructure chest plate
– High-performance polymeric material blend, graduated structure from centre to outside
– Ergonomically contoured for natural chest curve and optimum fit
– Soft airmesh body contact layer for maximum breathability and comfort
– Super lightweight construction
– Designed for track and sports bike riding suit use
The Nucleon KR-Cell CiR Protectors at £49.99 are genuinely impressive value for CE Level 2 chest protection. The Nucleon Cell energy absorption architecture, airmesh breathability, and track-specific ergonomic fit make this a capable and well-priced chest protector for circuit riders.
The Nucleon KR-Cell CiR Protectors deliver CE Level 2 chest protection with Nucleon Cell technology at £49.99 — making this one of the most accessible Level 2 chest protection options in the Alpinestars range. The airmesh back face and cellular energy absorption architecture make this a capable protector for track riders who want serious certification without a major investment.
1. CE Level 2 certification (EN 1621-3:2018 Level 2) for chest protection at £49.99 represents excellent value for the highest protection tier — Level 2 chest protection at this price is uncommon
2. Nucleon Cell microstructure designed for advanced energy absorption, adaptivity, and maximum breathability — the cellular architecture distributes impact forces laterally across the cell network rather than transmitting them to the chest
3. Airmesh body contact surface provides maximum breathability from the protector face against the rider’s chest, keeping the chest cooler during track use than solid-backed protectors
1. Chest-only protector covering the chest impact zone; riders who also want back protection will need the Nucleon Kr-Celli or similar back insert alongside this product
2. Ergonomic back plate design contours to the natural curve of the back, suggesting this is designed as a front-mounting protector within a suit or separate vest — riders should confirm fitment compatibility with their suit or jacket
3. The product name references KR (Karting/Racing) and CiR (Chest inner Rider), suggesting this is specifically designed for the riding suit environment rather than general jacket use
