I've put them on but they should come with elastic around the perimeter so they stay put or lanyards to attach to so they stay put in seats. Otherwise they are water proof.
I have a pair of black seat covers for my 4 Runner. Love them, well made. Fit is perfect. Arrived swiftly. Excellent value. Came with a personal hand written note too.
Dri Seats Waterproof Car Seat Covers
DriSeats Center Console Waterproof Covers 12" x 8"
