ModMax STAINLESS STEEL Piston Rings are a necessity for Supercharged, Turbocharged, High Boost, and High Nitrous Injected Modular engines. These rings are manufactured with exacting tolerances for OEM sized 1.5mm top groove, 1.5mm 2nd groove, and 3mm oil groove pistons. Our unique and exclusive design allows these rings to work on all Modular pistons with OEM sized ring grooves (ModMax, CP, Ross, Mahle, KB, Probe, Diamond, Manley...etc.) The rings feature a GAS NITRIDED Stainless Steel Alloy top ring engineered for instant seating, superior sealing, and optimum durability. In very high heat and cylinder pressures this material top ring will not get soft or lose tension, plus it will hold up its composition without flaking or chipping in the most extreme environments. THESE RINGS ARE A MUST IF YOU WILL BE RUNNING MORE THAN 12LBS OF BOOST OR HIGH AMOUNTS OF NITROUS OXIDE! The second cast iron rings feature a NAPIER Taper Hook Groove design for superior cylinder scraping reducing oil migration into the combustion chamber. Oil rings are a low drag, yet standard tension design for superior oil control for use in all naturally aspirated or boosted environments. The rings come in standard, +.020", or +.030" bore sizes with an additional .005" oversize for file fitting. NOTE: These rings MUST be file fit for each particular engine.