Originally Posted by Diesel911

The little O-ring is the only O-ring on the Turbo MW type Lift Pump that uses the Kit I posted the pic of with the hard Plastic T Valve in it (turbo MW Fuel Injection Pump).

Ask Stretch to be sure but I am guessing the 2 larger O-rings are used on the Lift Pump that has the Disc Valves like the one this thread is about (Valves similar to the Valves in the Vacuum Pump).