The Weller RTU 004 C MS X (T0050105299) RT Ultra Active Soldering Tip, Conical Bent, 0.4mm, MIL-SPEC, for WXUP MS Iron, is a high performance active tip for heavy duty applications and the largest components. The tip features a built-in sensor and perfect heat transfer, for the fastest heat-up and recovery time. The tip enables users to reduce downtime for a faster workflow and better results.