The Mini Excavator Track Roller/Bottom Roller for Kobelco SK042,SK45,SK50.etc: Amazon.com: Industrial & Scientific
Bobcat 337 341 435 Bottom Roller 6814890
Komatsu PC40-7 Bottom Roller - Mini Excavator Centre - Digger Parts
Prime-Line Gray Plastic Convex Wheel Mirror Door Bottom Roller N 7235 - The Home Depot
1 Pair Single Sliding Door Wheels Rollers Bottom Wheel Fixed Nylon Caster Pulley Runners Window Drawer Furniture Hardware - Door Rollers - AliExpress
Bottom Rolling / Supporting
WINSOON 4.8 in. Sliding Barn Door Floor Guide, 8-in-1 Adjustable Floor Guide for Bottom Roller and Wall Mount System(2-Pack) GCM5155x2 - The Home Depot
Bottom & Top Rollers for mining excavators and bulldozers - RTD Mining