?Great value and a quality product. I almost wish I had gotten swivel base but would not use for over a year.Camera invisible line when jaws closed and the play when open is due to backlash on nut that goes away on closing.The 123 block test was edge grip with 0.002" precision shim holding one from falling and need to use force to bring in 0.001" shim on other side of vise as per picture. Clamping pressure consistent across 6".Bottom is well ground as well, top jaws are not detectable by finger so < 1 thou.Happy with purchase, wish rotating base was available separately.Manual is horribly translated, worst Google translate seen to date.