THIS IS A PAIR OF AUTHENTIC GENUINE OLD SCHOOL TIRES. YOU GET 2 QUALITY MADE TIRES, THEY ARE STAMPED 20 X 1-3/8 ( 37 - 451 ). THEY FIT BRITISH E.5J AND AMERICAN S-5 / S-6 RIMS. I FOUNDED THEM FROM A SCHWINN WARE HOUSE I BOUGHT OUT. THEY WILL FIT TO SCHWINN STINGRAY FASTBACK BIKES AND OTHERS CARRY SAME SIZE AND ISO NUMBER AS WELL. THEY ARE A RARE SIZE TO COME BY, THE CONDITION OF THE VINTAGE TIRES ARE AT LEAST 8 OUT OF 10 CONDITION WITH MAY BE SOME TINY CRACK THAT IS HARDLY NOTICE BECAUSE IT IS OLDER AND BEEN SEAT FOR LONG TIME AT THE WAREHOUSE. THEY ARE TEST AND READY TO GO ON THAT SHOW BIKES OR RIDER BIKES, THEY ARE IN GREY COLOR AND LOOK FANTASTIC ON THE BLACK FASTBACKS 1960S BIKES.