An M.S.A. Mining Methanometer.
An M.S.A. mining methanometer type D6. 
Made from plastic. Size 6″ x 2 1/2″ x 2″.
Used for checking for methane gas below ground. Used with an extension a telescopic extension probe and rubber bulb, the probe would screw into the top of the detector which is situated under the yellow cap.
Out Of The Blue Artifacts A Library of a lifetime of collecting
				