Size:3.0mm*1.6mm*2.0mm. Quantities:1000units per color per bottle,net weight:about 55g. Color Available: #1 black, #3 dark brown, #5 brown, #6 beige blonde,#8 dark blond, #11 light brown,#13 light blonde.can match your hair perfectly. Silicone Nano Rings are used for Nano Tip stick hair extensions. Copper material with Silicon pipe,thanks to the small size can be attached to your hair easily and invisible .