Adapter bolts to stock 5 x 4-1/2" or 4-3/4" bolt circle hub or axle flanges when adapting to 5 x 5" bolt circle pattern wheels. Adapter is fitted with 5/8"-11 coarse thread studs and measures 1" thick. Adapters are bolted from the backside of hub or axle using 1/2"-20 mounting hardware (not-included). Not for use with additional wheel spacers and additional machining may be required for proper installation.