Compatible with Garelick hardware Provides solid base of support for a variety of seat hardwareAccepts Garelick fore and aft seat slides and 360° swivel spider combinationsAccepts seat slides: 22000, 75080, 75081, 75082, 75083Accepts spiders: 99023, 990362-7/8" diameter smooth stanchion tube, 9.25” diameter 6 hole base plate