angle and fit all stem sizes. Tool Steel Retainers provide the best of all valve train benefits: light weight, as well as exceptional strength and wear characteristics. Approximately 33% lighter than conventional chromemoly Steel retainers and only 2-4 grams heavier than titanium (depending upon application), they are made from high-grade Tool Steel, making them able to withstand even the most demanding Race applications. Developed using latest FEA and CAD software, these retainers are CNC-machined for consistent quality and Spintron-tested to extreme RPM.