4 Wheel P2750-EG Trolley Assembly Light Duty Electric Hoist Trolley Roller for use with 1-5/8" Wide or All 1-5/8" or Taller Strut Channel,Unistrut Accessories,Superstrut,2 Pack

as described

Solid bearings that fit well in the strut and move as they should. I'll be literally trusting them with my spouse's life—no reservations there. As another reviewer stated, they're a little bit gritty. I wondered if all U-Strut trolleys were that way, so I got a different pair (with two wheels, not four), and those were super smooth and silent (minus the sound of them against the strut, obviously). Still, these should work fine.

You get a pair of trolleys that allow you to use unistrut as track moving items easier. These medium duty units have formed metal and solid axles to sealed roller bearings. You can purchase the length of unistrut you need for the space you want to move. I only needed an 8' length as I was just attaching them to a 4' storage rack board to allow moving left and right to access behind as well and they worked great.

These trolley wheels are excellent for you track, or FasTrak. These were perfect to be able to mount some of my camera lighting on for a overhead dolly that I built. Easy to install just slide them in the channel.

A couple of the bearings on each of these trolleys are gritty when you roll them. They still rotate, but not smoothly as they should. Perhaps they will smooth out after a period of breaking in.

Outstanding trollies. Great for hanging shade cloth in front of the garage door to make the garage more bearable in the summer!

These 4 bearing trolley brackets have a weight rating of 1200 pounds each. The trolleys are designed for 1-5/8” unistrut track for hanging doors, winches or whatever you need to suspend. The brackets have threaded holes in the bottom for attaching your item. The bearings/ wheels are sealed for no maintenance and less friction.

4 Wheel P2750-EG Trolley Assembly Light Duty Trolley Roller for use with 1-5/8" Wide or All 1-5/8" or Taller Strut Channel,Unistrut Accessories,Superstrut(2 Packs)these are pretty good. i dont know if the "design load 1200lbs" is a fiction or not, i think if only using the center hole that could be a little tricky, maybe that refers to fastening to all three holes? anyway, i am not hanging 1200lbs i am hanging some doors for a slider door contraption. and for this they will be absolutely perfect. they rooll fine fit tall strut just fine, there is a little side to side play but the wheels are on the crimped part and just fine. basically just fine lighter duty trolleys.