Specifications:12-1/4" x 3-3/8" 8000# Forward Self AdjustingDirect Replacement Dexter 023-434-00,023-435-00Cast backing plate with 4 hole mountRated at 8,000 lbs. per axleSelf adjusting electric brake assembly keeps your brakes adjusted automaticallyAll brake parts are pre-assembled on the backing plate for quick replacementTypically, Dexter Drum will 8-285 cast into the front of the drum Replacing your Dexter Axle 23-434 and 23-435 electric brakesMount Bolt Spacing on both is:3 and 5/16th inches by3 and 5/8th inches For 12-1/4" x 3-3/8" 8000# Forward Self AdjustingDirect Replacement Dexter 023-434-00,023-435-00Cast backing plate with 4 hole mountRated at 8,000 lbs. per axleSelf adjusting electric brake assembly keeps your brakes adjusted automaticallyAll brake parts are pre-assembled on the backing plate for quick replacementTypically, Dexter Drum will 8-285 cast into the front of the drum Replacing your Dexter Axle 23-434 and 23-435 electric brakes Mount Bolt Spacing on both is: 3 and 5/16th inches by 3 and 5/8th inches Package Includes:Left-hand and Right Hand 12-1/4" x 3-3/8" electric brake assembly 1Part Number 23-434, 23-435, 023-434-00 023-435-00; Part Type Brakes & Components; Dexter Interchange Number K23-434-00 K23-435-00;;