The Wacker Neuson Concrete Vibrator Head is a hardened vibrator head for the modular, high frequency Wacker Neuson internal vibrator HMS. Complete induction hardened, highly wear-resistant steel vibrator head is 2in. (50 mm) diameter and 15.6in. (395 mm) long. Designed for extra high mean amplitude. Hybrid vibrator head shape. Vibrator head only (engine and flexible shaft not included, sold separately). Works with: M1500/120 Drive Engine (Model# 5100004500), M2500/120 Drive Engine (Model# 5100006000), SMOS Flexshaft, 1.5ft. (Model# 5100005706), SM1S Flexshaft, 3ft. (Model# 5100005707), SM2S Flexshaft, 6.5ft. (Model# 5100005708), SM3S Flexshaft, 10ft. (Model# 5100005709), SM4S Flexshaft, 13ft. (Model# 5100005710), SM5S Flexshaft, 16.5ft. (Model# 5100005711), SM7S Flexshaft, 23ft. (Model# 5100005712), SM9S Flexshaft, 30ft. (Model# 5100005713), BV 50A-H Backpack Vibrator (HMS) (Model# 5100041314)