The SPEC Stage 1 clutch disc is specified for SR20DET rear-wheel-drive applications and is sold as the disc-only option (for part number SN331). Presented as the replacement friction disc intended for that SR20DET RWD Stage 1 setup, it is offered to match the referenced part number for clutch service or rebuilds where the Stage 1 disc is required.
Spec SR20DET Rear Wheel Drive Stage 1 Clutch DISC ONLY (for p/n SN331)