T7 Size is 22 - 14mm. T3 Size is 16 - 10.7mm. T5 Size is 20 - 12.4mm. Other uses include eyelet holes for Tarpaulins, Banners, Pool Covers or general scrap-booking purposes. The Stud Press Machine can also be used to poke accurate holes with precision into Belts, Handbags or Leather crafts.
eBay