At left, an example of screw-knob style clamp. At right, an example of lever-release clamp.
These two clamps are exactly the same EXCEPT the way the clamp jaws open & close.
Lever-Release Clamps open & close by flipping a lever.
Screw-Knob Clamps open & close by turning a knob.
In the field, these two clamps function equally well. The lever-release clamp is faster & easier to open & close, and almost 90% of Really Right Stuff customers prefer them. But screw-knob clamps are tried & true, and some customers feel more comfortable with them. We offer both styles in a variety of sizes, and all of our ballheads are available with your choice of clamp.
Lever-Release Clamps are faster.
Lever-Release Clamps are easier to top-load.
Lever-Release Clamps use a cam mechanism to apply pressure.
Lever-Release Clamps maintain tension as they age.
Lever-Release Clamps operate flawlessly with all Really Right Stuff and Wimberley quick-release plates.
Lever-Release Clamps & Screw-Knob Clamps are equally strong.
Screw-Knob Clamps can be forced to apply more pressure than Lever-Release Clamps apply.
Screw-Knob Clamps are about 15% lighter than Lever-Release Clamps.
Screw-Knob Clamps are about one-third less expensive than Lever-Release Clamps.
Screw-Knob Clamps can accept Arca-style plates from most makers of such plates (but many Novoflex plates do not work in our screw-knob clamps).