Premium Quality Pistons + NPR Brand Rings Set for 1991-1998 Nissan 2.4L 240SX Altima KA24DE 16V DOHC .020"(.50mm) Ultra Performance Custom Made Premium Grade Aluminum Silicon Pistons. Best QualityUpgraded Made-in-JapanGenuine Nippon Piston Rings (NPR name brand). Premium quality nitrite hardened steel rings.Withstands extreme heat. Meets or exceeds OEM specifications.Easily lasts 150,000+ miles. Excellent for street & performance vehicles!