A selection of the various replacement rubber washers used on standard S30 valves and Pin valves. Reading clockwise from the top right hand corner we have:
The Pressure Relief Rubber (1104) fits over the larger, fatter section of the valve that is outside the barrel body and directly below the screwthreads.
The Inlet Rubber (1105) is the small rubber tube that fits over the inlet post of the valve that sits inside the cap/barrel.
The O-Ring (1106) fits inside the valve and provides a good seal around the neck of the Gas Bulb/Hambleton Bard clinder to prevent gas leakages during repressurisation.
The Sealing Washer (1107) fits outside the barrel, between the metal flange plate and the sealing nut (which is screwed to teh underside of the cap). It is NOT the flat white O-ring that fits between the cap and barrel - that is part no 1116 and is displayed in the "Replacement O-rings" section of this category.