Bolt Fitting Ball Transfer Units. Pre-lubricated ball transfer units to move or transfer loads in any direction. Max speed 1m/sec. Manufactured to general tolerance of ±0.3mm. Plated with zinc/iron alloy finish for protection in use. Operating temperature -30°C to +70°C (continuous use, depending on seals used). Pattern Heviload 1 Bolt fixing Two spanner flats for fixing and removing Bolt type fitting