When I first started designing and hardcrafting my own jewelry, I really had no sense of bead “sizes” a 4mm and an 8mm bead really meant nothing to me. I would order a lot of my gemstones online and would be dissapointed, because I’d miscalculated the size of my bead. UNTIL… I decided to get a bead guage! What a great tool. I highly recommend it to EVEYRONE in the handmade jewelry biz! It makes life easier and trust me.. Useing a ruler just isn’t the same!