Full-Sized Telephone Butt Set, Waterproof and DustproofTelephone Test Butt Set, Water and Drop ResistantMT 8100 Butt Set comes with all the functions you need to be more productive in the field. It was approved by IEC EN 90529 IP54 for waterproof and dustproof test, and features the latest improvements to drop protection realiablity. MT 8100 is a smart operation unit used by installers, repair technicians and other authorized personnel to test copper wire voice subscriber lines. It is easy to use,