This is a second cam check assembly for the Wilkins 350, 350A, 350DA, 350ADA, 375, 375A, 375DA, 375ADA, 450, 450DA, 475, & 475DA series assemblies. This is a complete second cam check. The check is held in place by a two metal retainers. Use caution when removing the retainers as they often break. Replacement retainers are included. Genuine Zurn/Wilkins repair parts. No special tools are required for servicing.