Our single-echo Portagauge™ 3 has been in service and upgraded many times for 20 years. Known as the “low cost Marine Superintendents Thickness Gauge” it is widely used in the shipping industry. Small, hand-held, highly versatile and accurate it is now joined by the multiple-echo metal-only Portagauge™ 4 – so that it takes only the metal reading not its coating as well. We now have a range of ultrasonic sensors to work aboard ships but also to test wall-corrosion of fire safety cylinders and gaseous fire extinguishing and fire sprinkler pipework so that testing can take place cleanly and non-invasively, without disturbing the system.