ProMaster’s Nodal Sliders are compatible with ProMaster tripods, heads, and gimbals that use the Dovetail Mounting System, as well as other Arca-type products. A Nodal Slider allows a lens to slide backward and forward on a tripod head, so that the lens’ nodal point (sometimes called the “no-parallax point”) can be perfectly centered over the head. Centering the nodal point means you can rotate the camera and lens on the head without an unnatural arc in the panning movement. This helps photographers create perfectly stitched panoramics, but this movement can also be very helpful in video work. A Nodal Slider can also be used to change the mounting direction of a camera by 90 degrees. Some tripod heads, like most gimbal heads, only allow front-to-back mounting of the QR plate. When using an L-Bracket or a QR plate that’s mounted in a side-to-side direction, a Nodal Slider will allow you to attach the camera to the gimbal without adjusting the plate or L-Bracket. Additional features include: Integrated bubble level Strap slot Sliding 1/4"-20 mounting bolt Numerous 1/4"-20 mounting ports Scales for repeatable setups