Winbag inflatable air cushion leveling tool. Ideal for installing windows, doors, cabinets, and household appliances. Does not damage surface when shimming. Works in gaps from 3/32″ to 2″. Maximum load capacity is 300 lb. Additional Winbags can be added to larger jobs to increase capacity. Features a hand operated pump that inflates the air cushion and holds heavy objects in place when leveling. Release valve makes even the smallest adjustments easy. Reduces installation time and reduces the number of installers needed to complete the job. Reusable.