What is the measurement of the throw?

I purchased the throw assuming it would be 60 x 80 but IT IS NOT. It’s actually 50 x 60, the average size for a throw blanket.

How do I wash and dry this item without it losing its texture?

I found the secret! Heat is the enemy with these kinds of blankets and throws. Wash on cold, gentle cycle, and either air fluff in the dryer (takes two and a half to three times as long, but it will dry), or just hang over a few chairs to air dry. No fabric softener. Half as much laundry soap as you usually use. You can also add a cup of water mixed with 1/4 cup of vinegar (white or apple cider) to the rinse water. That cuts any soap residue, acts as a softener, and does not make it smell like vinegar. But, the biggest issue is any heat will destroy the softness...it literally melts the fabric just enough to where it’s not soft, or as soft, anymore.

does this item stay on longer than 3 hours?

“Stay on” ??? Not sure what you mean, it isn’t an electric blanket. I guess it stays on as long as the user doesn’t kick it off ! Hahahaa ! I bought one for my hubby for watching tv and he loves it. Hope that helps.