a closeup photo taken on two wheels of a folded push load trolley

pair pairs two wheel wheels front back folded fold folding pull push pushing loads load trolleys trolley rest resting wall walls tool tools heavy haul carry carrying move moving mover movers friction frictional brake brakes braking platform platforms capacity maximum handle handles bar bars grip gripping hold holding black swivel swivelling maneuver maneuvering store logistic logistics logistical common warehouse warehouses inventory inventories shift shifting