High quality, black anodized aluminum TrackDogs™ are sized to fit 20mm holes on MFT style tops. Only 18.5mm tall, so they sit flush with 19mm or 3/4" MFT tops. They have a 1/4"-20 thread for adding a hex head bolt which slides into the TrackTubes t-track. Used to secure MFT tops, sliding stops, and other accessories used with MFT style tops. To tighten, use a coin or other tool in the slotted top. Priced and sold in pairs (2) only. Hex head bolts not included. Price also includeds FREE Shipping.