Compression sleeves made of copper provide maximum reliability and long life. It is recommended that only copper sleeves that are manufactured to the US Military Specification (Mil-Spec) MS51844 be used in cable connections where reliability and general safety are a primary concern.
The Locoloc® brand copper sleeves sold by Loos & Co. Inc., Cableware Division are manufactured to the US Military Detail Specification MS51844. The latest revision of this specification is MS51844D dated 19 April 2007. A copy of MS51844D can be found here..