3M™ Dynatel™ dyna coupler is a tool specifically designed for locating underground facilities. It allows coupling of RF trace tone to large diameter pipes, bundle cables and cables enclosed in accessible non-metallic ducts. This coupler operates at a temperature range of 4 to 122 deg F. 3M™ Dynatel™ dyna coupler can withstand short time immersion under water. This coupler is compatible with 2273, 2210, 2250M, 2250, 2273M™, 2220M, 2550, 2573 model locators.