Vintage Singer Treadle cabinet wheel / castor. This is the earlier 1/2" wide version, please note that it is not compatible with later treadle frames that use the 3/8" wide wheel. Measures approx 1 1/4" in diameter and 1/2" wide with a 1/4" center hole. No axle / pin. Very good vintage condition, has been gently cleaned but the original patina remains intact.