New in Box. Never used. Camco 44510 Heavy Duty Leveling Blocks, Ideal For Leveling Single and Dual Wheels, Hydraulic Jacks, Tongue Jacks and Tandem Axles (10 pack, Frustration-Free Packaging) The Camco Leveling Block 10-pack allows you to stack the interlocking blocks to the desired height for safe and easy leveling. These blocks can be used with single wheels, double wheels, hydraulic jacks, tongue jacks, stabilizer jacks, 5th wheel jacks and tandem axles. Camco’s RV Leveling Blocks make it easy to customize your levels. Simply stack the interlocking blocks together to your desired height. They have a strong, durable construction and a solid bottom to help keep them from sinking into the ground. Engineered with a patented design to optimize both strength and weight, resin is UV stabilized and built to last even when exposed to sunlight for extended periods of time. Bright, visible yellow color helps you see them so you don’t leave them behind. They can also be used to help prevent your stabilizers from sinking in soft ground. Camco's RV Leveling Blocks measure 8.5 inch x 8.5 inch and can be used with stack jacks, trailer tongues, 5th wheel jacks and swing arm supports. If dirt or debris build up in the leveling blocks, just knock it off and hose it out before storage. Product includes a zippered storage bag with handle to keep them all together when not being used.