Greddy Type-S Radiator Breathing Tank - P/N: 12400903 Product Model: GRD-12400903 FITS: NISSAN / MITSUBISHI Breather Tank, S-type cap NOTES: use w/ water sensor adapter Radiator Breather Tank Designed originally for racing engines, today’s compact production engines can also benefit from the used of GReddy’s Radiator Bleed Tank. By mounting the tank high up in the engine compartment, you can be assured that of a fully filled system with room for air expansion, thus reducing chances of overheating due to air-lock. Block-off radiator cap included.