Semtex

Semtex is a general-purpose plastic explosive containing RDX and PETN. It is used in commercial blasting, demolition, and in certain military applications. Semtex became notoriously popular with terrorists because it was, until recently, extremely difficult to detect, as in the case of Pan Am Flight 103. For its original military use it was manufactured under the name B 1. It has been manufactured under its current name since 1964, labeled as SEMTEX 1A, since 1967 as SEMTEX H and since 1987 as SEMTEX 10. The composition of the two most common variants differ according to their use. The 1A (or 10) variant is used for blasting, and is based mostly on crystalline PETN. The version 1AP and 2P are formed as hexagonal booster charges; a special assembly of PETN and wax inside the charge assures high reliability for detonating cord or detonator. The H (or SE) variant is intended for explosion hardening.