Note* We have modified the 263-10 Retainers to work with our new 270 Dual Valve Springs for the Racing Lawnmower Engines. 

These Retainers and Locks fit the Briggs Model 31, and Model 33 OHV Intek Single Cylinder Engines and the Briggs Model 40, Model 44 and Model 49 Intek V-Twin Engines. 

They will also fit the Briggs Model 35 and Model 38 Vanguard V-Twin if using the stock split lock retainer valves, they will not work on valves that use the slip-on retainers. 

Our Billet Retainers are lightweight to stabilize the valve train allowing the engine to turn more RPMs. 1 gram on the valve side is worth about 40rpms. The billet retainers are also hard anodized in our factory red for durability and a great look.