You are buying a new BZ-12 pre-loaded ball slide. Comparable new units sell for approx $105.00, so at this price you cannot go wrong.
See specifications below.
Brand Ball Slides Inc Carriage Interior Width 1.1 inch Carriage Length (Center to Center) 3 inch Carriage Overall Length 4 inch Carriage Overall Width 2 inch Carriage Width (Center to Center) 1 inch Measurement System Inch Load Capacity 40 Rail Overall Width 1 inch Travel 3 inch Type Compliant-Type Ball Slide Other Information Tarriff Code 820790 Manufacturer Part Number 24-3C Line Drawing Drawing Key A 3 inch B 1 inch D 1.1 inch E 1 inch L 4 inch W 2 inch
These pre-loaded ball slides provide an acceptable level of accuracy for most linear motion applications (.001"/inch) at a considerably lower cost than more expensive ball slides or crossed roller slides. The compliant slides use a conventional hardened steel rod raceway and balls, but also incorporate an elastomer spine and shock-absorbing back-up gib. This unique combination provides even and continuous preload, while minimizing the effects of impact and shock. This slide can also tolerate contamination and operate over many million cycles without lubrication. Available with either a compliant preload or a hard gib preload. 8-32 thread mounting holes.