Canton 21-850 Rear Main Seal Adapter Converts 1 Pc SBC To 2 Pc Seal. This SBC rear main seal adapter converts? 86 and newer blocks with one piece rear main seals to accept an older style two piece seal crank shaft. The adapter is essential when installing an early style pre-? 86 & newer blocks. When using this adapter an oil pan for a pre-86 block with a right side dipstick must be used. Made from Billet aluminum, hardware included. We warrantee and represent that the goods are as described in the above listing. We specifically disclaim any implied warranties of title, merchantability, fitness for a particular purpose and non-infringement. Customers should satisfy themselves that any item choice made is suitable for their intended purpose or use. We pride ourselves on our customer service. Canton Racing Products has been servicing the needs of the racing and high performance community since 1981. From our headquarters in Connecticut we design and manufacture high quality performance automotive parts for use across the world. Focusing on engine oiling and cooling systems our product line includes, oil pans, windage trays, oil and fuel filters, oil accumulators, oil and coolant catch and expansion tanks, coolant accessories, and many other products for race and street. You may also be interested in.. View more great items.