The V-Lock Assembly Kit from ElementS comes with a Female V-Dock and a Male V-Lock. It is a part of the popular ElementS V-Dock and has multiple mounting options. You can attach the Assembly Kit directly to a top mount, or the ElementS Cheese Plate, or the ElementS Cheese Stick top handle using a 1/4"-20 low head socket cap screw. The 1/4"-20 tapped hole in the center can be used for extra mounting options.
You can mount this assembly directly to the Shoulder Pad Mount on the Mantis. It also makes a great mounting point for a Red Drive equipped with the ElementS Shock Mount, or the Red Battery Plate equipped with the ElementS Battery Interface Plate with V-Lock. By mounting the V Lock to the back of shoulder mount, the gravitational pull is directed towards the camera center thus reducing the load on the camera.