This front motor mount spacer place replaces Harley-Davidson OEM # 438-48 / 24795-48. This spacer works to mount Knucklehead engines in 1948-up frames. The spacer plate is 5/16 inches thick and is raw steel. As usual, tighten down your rear motor mount bolts first and check if the front motor mount needs shimmed, even when using this spacer. It is common for people to not shim the front mount and tighten everything up, which can result in a broken motor mount ear on the engine case. Ensure that it is perfectly level (no gap) on all four motor mount bolts before torquing. Longer front motor mount bolts will be needed due to the spacer, 74 cubic inch Knucklehead / Panhead bolts 1946-1957 work perfectly. Made in the USA.