Here are TWO seal kits that are correct for the Smith & Wesson models 78G & 79G CO2 pistols.

They include all of the most common O-Rings that are needed to bring your

pistol back to life. Enough for two complete pistol re-seals. The kits include:

(2) Piercing Body/Gas Cap Seals (White Urethane O-Ring)

These white urethane seals are widely regarded to be of the highest quality and most durable available for your CO2 tube cap application.

(2) Piercing Pin Seals (O-Ring) 

(2) Valve Body Plug Seals (O-Ring)

(4) Valve Connector/Transfer Port Seals (O-Ring)

(4) Breech Bolt/Probe Seals (O-Ring) (Slightly smaller one is for 79G - the larger one is for 78G)

Thank You.