MT5011 Medium-Duty Logic Trolley Operator by LiftMaster - For Use On Standard Lift Sectional Doors BG770 Barrier Arm Gate - for industrial applications overload protection supports 100 cycles per hour by LiftMaster The LiftMaster 3950 jackshaft door operator is designed for use on commercial rolling sheet door applications only.  The 3950 commercial jackshaft can mount of either right or left hand side.  It is ideal for self-storage facilities.