Review on Uxcell Mounted Pillow Insert Bearing Power Transmission Products and Bearings by Mike Barnes

Unfortunately they are of very poor quality. They stick so tightly that you have to use a long screwdriver and pliers to move the gimbal. Lubricants don't help. I will spend a little more and get another brand. To be clear, the shaft bearings work well, but since the gimbal sticks very poorly, alignment is difficult. I hate giving a bad review, but that's definitely only one star.