Jack Axle Roller
Makes jacking up the car and rolling the rear axle a breeze, lubing the chain, and checking stagger. No more binding on the chain as you roll the axle, the (4) bearings keep the axle just suspended enough to let the axle roll smoothly
Comes with (4) bearings & (4) rounded head bolts
Anodized black with engraving
Designed for use with harbor freight aluminum jacks
Comes in 2 options:
(To figure out bore size take off rubber boot in middle of round jack plate used to lift, small bore pin head size is 1-1/8 diameter, big bore pin head size 1-1/2 diameter)
Big bore for the larger harbor freight aluminum  jacks (head pin size 1-1/2 diameter), then also a smaller harbor freight aluminum jacks (small bore head pin size 1-1/8). Only difference between the two is the bore size in the middle to accommodate for the jack that you already have.