Earl’s Engine Oil Cooler Adapter LS0012ERL. Earl’s and Holley billet side mount oil cooler adapters are the slick way to add an oil cooler to your LS engine. The slim design of these adapters clear most headers and other components and feature 10AN male connections. These adapters are black anodized and use O-Ring seals for a leak free installation. Add an Earl’s Oil Cooler and AN plumbing to complete the installation. 10 AN Male Connections. Slim Design to Clear Most Headers & Other Accessories. Ideal for Engine Swaps & High Heat Applications. (2) 1/8 NPT Ports. Approximate Overall Dimensions: 3.110″ Long x 3.000″ Tall x. 50th Anniversary Edition Pace Car. Adapter AN Size (A). Adapter AN Size (B). Adapter NPT Size (C).