JE Pistons GM LS ASYM FSR Flat Top 3.900 STRK 4.010 Bore - Single Piston

JE Pistons asymmetrical FSR (Forged Side Relief) piston line incorporates modern forging design with a larger skirt on the major thrust side and smaller, friction-reducing skirt on the minor thrust side. Combined with precision CNC machining, the result is a high-strength, lightweight piston that is extremely durable.