OUR PART # MLM-M12CS
This Mega-Coupler from The Light Source known as MLM1/2CS replaces the standard Hex Head bolt with a flat head countersunk bolt. It comes available with a 1/2" flat head base or a 3/8" flat head base to fit a flat head bolt. An Allen wrench is required to adjust this bolt.
Also available with an M12 flat head metric bolt (40mm length) to fit the Martin Mac 101 LED light or other European fixtures. Order codes for counter sunk couplers with metric bolts are MLB-M12CS and MLM-M12CS.
You can also replace the standard Light Source wing nut with a steel wing nut.