5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm crochet needles.  Comes with 4 handles and 8 needles. Glue the two halves of each piece together and then screw the needle you wish to use into the handle you prefer. When you are deployed and shipping takes a month sometimes you have to improvise to be able to enjoy your hobbies.  I whipped these up so others could enjoy their hobbies of crocheting.  They work fine, I realize they aren't exactly like the ones you might buy but they look pretty cool.