Linear guides featuring carbon steel linear rails, U-shaped and zinc plated, with standard mounting holes and LaZer Straight™ bolt-on alignment for fast, dead-accurate installation. Lightweight anodized aluminum carriages ride on preloaded, lubricated-for-life sealed roller bearings (52100 steel or 440 stainless) with integral wipers. An open-end wrench is included for easy preload adjustment. Available in 20, 30, and 45 mm rail widths with continuous lengths up to 6,000 mm (236 in), these Commercial Rail guides deliver high load capacity, excellent corrosion resistance, and true “set-it-and-forget-it” performance in the harshest, dirtiest environments — requiring only occasional rail greasing every 50,000 cycles.