"Love 'em: Suitable for immobilizers and wheel chocks
Both hands are required for installation, one hand holds the device, one to open or close I'm sure of their design, so I don't use them, I use them Master Lock combination padlocks.
Pros
X-TYPE WHEEL STABILIZER - Provides additional stability and prevents tire slippage by exerting opposing forces on the two tires. Extendable from 2" to 10". Universal fit for campers with tandem axle , vans, trailers, etc.