O ring for the air conditioning system -06. This O ring measures approx 10mm outside diameter and 7mm inside diameter. The other O rings used are -08 TVR P0044, -10 TVR P0045, -12 TVR P0203. Should always be replaced if disturbed to ensure integrity of the air conditioning system. The No 6 O ring is generally used on the high pressure side of the system between the condenser and the expansion valve.