MSW’s Take: We have multiple sets of these dollies in our shop. It’s the only way we can cram 16 cars inside. They also elevate lowered race cars just enough to allow a standard floor jack to slide under and reach the center jack points. Much higher quality than what can be found at Harbor Freight (we tried.)
These dollies are sold as a pair. Made of aluminum, with quality casters (two locking per dolly.) Easily position vehicles into tight spaces.