These economical over-the-road heavy duty truck axle shims a re our lowest cost option. With average compression strength and hardness these shims are available in a large variety o f sizes and offer the technician a cost effective means to c orrect caster on over-the-road trucks and trailers. NOTE: Or dering one Part Number supplies Six Shims in a box. When pla cing order spring pad length and width are needed. California Residents WARNING Product appearance and features may vary in the market as design changes, improvements and modifications are implemented.