Profile: Refinery Supply Company, Inc. is a producer of oil & gas and laboratory equipment. We offer flexible connecting hoses, safety equipment & supplies, compound microscopes, vacuum pumps & accessories and portable gas monitors. Our hanna checker 1 pH tester supplies readings on a LCD. It is suitable for checking electrodes in pipes, tanks and various industrial applications. Our flexible connecting hose comes with stainless steel knurled connectors that can be connected without the use of a wrench.