Review on ⚙️ UCF201 8 Self Alignment Pillow Bearing: Superior Pieces for Precision Performance by Brandon Plowden

This is exactly what I expected. 2 floats smoothly in the pockets. The other two needed some penetrating lube and were easily loosened with a rubber mallet to loosen them up. Just in case, I ordered twice what I needed but paid less than I paid for 1 precision cast support block. If you want something super accurate, pay for it. If your project has some room for slops, they will work just fine.