A Mines Rescue Team Members Belted Harness.
A Siebe Gorman Proto MK 4.
It has the “ACME RESCUE” Rubber bulb Whistle, Nose Clip, shoulder straps a large front pocket to hold the Breathing Apparatus and a bolted bracket at the back to hold the Oxygen tank. Made from Canvas, Leather Felt and Iron. (back view).
Below is an original N.C.B. Mines Rescue Signalling Instructions Card.