Don't do it. I posted a thread complaining about my TuffRider sheet that leaks completely thru after about 15-20 uses, never been washed with detergent so no harm done by that.
I decided after owning TWO TuffRiders that leak, that sometimes, you do get what you pay for. I have a 10 year old Weatherbeeta that has been washed in non-horsey-laundry detergent and that still doesnt' leak.
I'll never buy another TuffRider
"If you think nobody cares about you, try missing a couple payments..."