Contains replacement components for most PetSafe In-Ground and Wireless Fences (excluding Stay & Play, Free to Roam, UltraSmart In-Ground and YardMax). Includes long and short (standard) contact points. The washers are used to keep the receiver attached to the strap. Protective clear caps help to keep water and debris out of the correction level adjustment button. The 4 screws are used to replace the receiver screws on Stubborn Dog In-Ground Fence receivers.