Size:4.0mm(outer diameter)*2.0mm(inner diameter)*3.0mm(length) Quantities:1000units per color per bottle,net weight:about 58g. 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 lined micro rings beads are used for (0.5g)/strand I Tip stick feather hair extensions.k feather hair extensions. Soft silicone lined inside micro beads,do not damage to your own hair,the silicon pipe can hold the hair tightly prevent the extension from sliding. Silicone Micro beads for hair extensions,thanks to the small size and light alumium weight can be attached to your hair easily and invisible.