"This pair of Tow Zone Hydraulic Drum Brakes features aluminum wheel cylinders and stainless steel springs. Drum Size in. 10, Brake Type Hydraulic, Hubs Included No, Brakes Included qty. 2. E-coat drum brake assembly Aluminum wheel cylinder Stainless steel springs Brake pads are bonded and riveted with bronze rivets to backing plate Includes left and right hydraulic drum brakes for one axle Does not include brake drum hubs."