The 6" Ames 3000SS Silver Bullet Series Double Check Detector Assemblies began production in 1998 and are still being produced. They are all stainless steel body devices. Please be sure which model you have as the "SS" and "SE" models use different repair parts. They utilize a single victaulic cover with two self contained plastic cam checks that thread into the body. There are no rubber repair kits available for the 3 - 6" sizes, only complete cam checks. The 3000SS features a bypass assembly to meter water usage. Although specialty tools are not required for servicing the device, there is a handy cam check tool available, designed to save time and prevent damage to the cam checks.The 2 1/2" Ames 3000SS Silver Bullet Series Double Check Detector Assemblies began production in 1998 and are still being produced. They are all stainless steel body devices. Please be sure which model you have as the "SS" and "SE" models use different repair parts. They utilize a single victaulic cover with two self contained plastic cam checks that thread into the body. There are no rubber repair kits available for the 2 1/2 - 6" sizes, only complete cam checks. The 3000SS features a bypass assembly to meter water usage. Although specialty tools are not required for servicing the device, there is a handy cam check tool available, designed to save time and prevent damage to the cam checks.