Utah Highway Patrol officials say the man was driving southbound near mile marker 353 about 10:45 p.m. Monday when he hit the debris in the roadway and went down.
A helicopter ambulance was dispatched, but the man was pronounced dead at the scene.
Officials say he wasn't wearing a helmet.
Troopers say they're not sure how the mattress ended up in a roadway, but are looking for its owner.
The crash is under investigation. The man's name has not yet been released.
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