Underwear Bottom FR Black Medium SFI 3.3

The Underwear Bottom FR Black Medium SFI 3.3 from RaceQuip is a critical base layer for any serious motorsports competitor, engine builder, or performance driver. This fire-resistant undergarment serves as your first line of defense in high-heat racing environments where standard cotton or synthetic clothing simply cannot withstand extreme temperatures. Whether you're running a turbo-charged street car at the strip, competing in road racing, or working extended sessions in an engine bay, these FR bottoms provide essential thermal protection that complies with SFI Foundation specifications—the gold standard for motorsports safety gear across North America.

Constructed from Nomex fire-resistant material, the Underwear Bottom FR Black Medium SFI 3.3 offers superior flame resistance and heat dissipation compared to conventional athletic wear. Nomex fabric has been engineered to resist ignition and self-extinguish when exposed to open flame, making it the preferred choice for professional drivers, pit crew members, and fabricators working near fuel systems or exhaust components. The medium sizing ensures a snug, comfortable fit that layers effectively under your racing suit without bunching or restriction, while the black color hides wear and maintains a professional appearance across multiple racing seasons. SFI 3.3 certification means these bottoms meet rigorous flammability standards and have passed independent testing for durability and heat resistance.

This product is essential for sanctioned racing competitors, high-performance mechanics working in engine shops, and dedicated enthusiasts who take safety seriously during intense driving events. The medium size provides optimal fit for average-build drivers and crew members, eliminating the discomfort of oversized or undersized protection. Installation is straightforward—simply wear as a base layer under your racing suit or work gear—and maintenance is hassle-free since Nomex withstands regular washing without degrading its fire-resistant properties. Whether you're preparing for your first track day or maintaining a full competition schedule, the RaceQuip Underwear Bottom FR Black Medium SFI 3.3 delivers dependable thermal protection that keeps you focused on performance, not safety concerns.