By Baird & Tatlock (London) Ltd. Stores reference 6D/421. 'Tester, Leakage For Valves Of H.P. Gas Cylinders MK.II & VIIA'. Glass testing tube with an internal glass 'swan necked' tube. These were used to test for leaks in the CO2 bottles of the 1941 pattern Mae West, Harnessuit, airborne lifebelts etc. The rubber bung and washer have 'stuck' to the glass but may loosen if placed in warm water. Otherwise in excellent unused condition in the issue box. complete with instruction leaflet. One for the serious collector! Please note that the CO2 bottle shown is not included in the sale. We have four available, priced individually. Stock code O18002-5.