Magliner 55 x 96 heavy duty ramp. ~12" high (the legs are buried some in the pic), it's 50" between the curbs
The internet thinks this is either a curb ramp or a dock transition ramp - either way it's really heavy duty and is built to hold some heavy traffic
I don't think magliner even makes them anymore but Uline has some kind of like it for $1500 and up.
I'm delivering some stuff to midland this month (November) and it would be super easy to throw this onboard and bring it along for a very small shipping fee (like $100)