This is a replacement master cylinder for a Model 10 or 20 disc brake surge coupler manufactured by Titan / Dico that includes the Side Mount Brackets.  Fits all Titan / Dico model 10 or model 20 surge brake couplers.  This master cylinder is designed to work with disc brakes.  Its an easy bolt on installation for replacing your old worn out / blown seals master cylinder.  Comes with everything pictured: the master cylinder, boot, lid, gasket, and cap.  Titan part number 4749501042.