1. Color -Black (#1B) can be colored/bleached.
2. Just like coloring natural locs or natural hair,  bleaching and/or coloring may weaken and potentionally alter the texture of the hair/loc.
3. The Skinnier (ie. small, extra small) the loc extension, the more susceptible it is to breakage and damage from bleach and/or color.
4. Its less damaging to purchase lighter color locs and color/dye them darker than it is to purchase dark and bleach light.

Although loc extensions may be shampoo'd , it helps to wait as long as possible before the first shampoo, most will wait 4-6 weeks. 

Do NOT install to wet or damp hair.