Three 3 / 8 " and ten 1 / 4 " threaded holes on each side for mounting articulating arm, LED panel and others You can also use it as raised cheese mounting plate for most digital camcorders and DSLRs Suitable for 501HDV, 701HDV and EI717 Works with 65mm 75mm hydraulic head Designing for use with tripods and camera pulleys, the bowl Adapter allows you mount bowl type video camcorders fluid head onto your tripods with a 3 / 8 " screw studs camera pulleys with 3 / 8 " screw studs