BLOX Racing retainers are CNC-machined from the highest quality titanium available on the market. These Ti retainers are machined to exact specifications and help reduce the overall weight of the valvetrain area. As a direct result of the reduced weight, RPM's are increased. Each retainer provides assurance from premature wear associated with high RPM's and mileage. Set includes 16-piece titanium retainers. Made in the USA. Engine Applications D16Z6 & D15B (JDM variant) D16Y8