TRD Resin Racing Oil Cap MS112-00001. The cap is a threaded screw type and will fit any Toyota that has an M37×P3.0 threaded valve cover. The most popular application is Toyota legendary 3S-GE Beams engine. The resin cap corners have holes for spring locks assuming use in motorsports. A spring lock can also be applied. (Refer to the photo) By applying a spring lock, it is possible to prevent loosening and falling off engines with intense vibrations and hard-circuit driving. It is also used on the Altezza engine that competes in super endurance races. * Springs for spring lock are not included.