JMI 5/8″ Speed Dial Drill Adapter for 5/8″ Leveling Screws – New Model Medium Heavy Duty and Large Wheeley Bars Quickly assemble JMI Wheeley Bar systems with the JMI Speed Dial Drill Adapter for New Model Medium Heavy Duty or Large) Wheeley Bars. Will not fit Medium Wheeley Bars or some older models of Medium Heavy Duty or Large Wheeley Bars with 1/2″ Leveling Screws. So measure and make sure that your leveling screws are 5/8″ diameter. This portable drill adapter helps quickly and easily adjust (raise or lower) leveling screws on any Universal-Style Wheeley Bars. Cuts assembly time by 50% or more! The Speed Dial adapter fits into any portable drill. Simply place the claws of the adapter over the leveling screw handle and use the drill to quickly turn the screw up or down as necessary to level JMI Wheeley Bars.