Product Description Specifications Precision machined from 6AL4V titanium, these retainers feature better material consistency and bullet proof durability. These 10 degree retainers fit engines with 1.500"-1.550" OD valve springs such as our 26094, 955 and 943 springs. Category: Engine Components>Valve Springs, Retainers Core: N LTL: N MPN: 727-16 Proposition 65: Y Special Order: Y