Collars weigh exactly 5kg, work really well. I'm using on a non calibrated plate set which had a ton of wobble and would push loose any collars I used; including higher end lock jaws. The Strongarm take the slack out of the plates and do not move at all. I would like to see a larger arm for more leverage on the part that screws into the barbell to make it easier on my hands. I simply use small pipe tool over the arm to secure tightly if I need to. The tool is from IKEA furniture and works really well to fit over the strong arm lever. So far though finger tight has been plenty secure.
Note I do not use them for oly lifts but for powerlifting. If you are looking to keep your deadlifts with 4 or 5 plates secure during reps with cheap plates these will do the trick. They also double as comp mock collars since they are calibrated!
Strongarm was also great and plan on ordering better plates from them. 5/5 stars from me, even without the longer screw arms for the price they work really well and it would take $150 USD to top them.
