Iowa Customs patented seat base adaptors are the solution for added leg room and adapting aftermarket or OEM seats without drilling holes in your floor. Each base adaptor is manufactured to match your specific brand of seat, making installation simple. Adaptors come with all mounting hardware included. Fits Peterbilt 379, 386 & 389. Finish options include BILLET ALUMINUM, CHROME PLATED, or powder coat colors: BLACK, RED BARON, CRYSTAL WHITE, POST OFFICE BLUE & YELLOW.