Wiktionary
winkers
n. 1 blocked leather eye shields attached to a (usually) harness bridle for horses, to prevent them from seeing backwards, and partially sideways; blinders in (USA). 2 a fleece cover wrapped around the cheek strap of a racing bridle to limit the rear vision of racehorses.
Usage examples of "winkers".
He got out and fixed the winkers, then put his hands as far as he could reach into his pockets--from the position of his trousers he could not possibly reach bottom.