With the SKB-710 Amp Case, your amp is held in place on a rugged rolling Velcro-covered board with patented adjustable corner cleats and a secure reverse-cinch belt. When in use, the amplifier sits securely atop the cover at a height that allows better sound projection. Made of rotationally molded polyethylene for road ready strength and durability. The amplifier case has 3" locking wheels. SKB is a premier supplier of instrument and gear cases. They build their products with military-spec, ultrahigh molecular weight polyethylene and premium hardware. All SKB hardshell cases are unconditionally guaranteed forever. That means if you break the SKB-710 case, they will repair or replace it at no cost to you.