Truma Pistol Grip Water Pump 'O' Ring x4 TR0801

The Truma Ultraflow Replacement “O” Ring Kit comes with two different sized pairs of ‘O’ rings to accommodate the two different inlets. The instructions are included in the kit and state the following for correct fitting. 
Generic Replacement “O” rings for the Truma Ultraflow water pump pistol grip
Two pairs of different sizes enclosed
Instructions enclosed stating correct sizes to be used