If it's Rhino, it should have a badge saying so up at the front of the box. If you have a rollup tonneau, it may be hiding it.
Rhino-Liner is pretty stout stuff. It's been in the back of my Silverado for 9 years now, and has been doused with acetone, oil, paint thinner, countless pieces of lawn equipment, tools, floor jacks, compressors, lumber, construction debris, metal, and an airborne 550 lb. coal stove that bashed in the bed, but didn't even touch the liner!
My tailgate gets used as a workbench daily for small power equipment repairs. Still holding up! They laid it on pretty thick too - not sure if the newer procedures use as much product. Seems everyone has cheaped-out on everything lately.
But, even the best liner ain't worth s*** if it wasn't prepped right ...