UEi Test Instruments designed the CH3 Hook to complement the DL379 and DL389 by enabling to professionals an easy and safe way to take measurements in hard-to-reach locations. UEi Test Instruments has over 45 years experience designing and manufacturing a broad range of award-winning, industry-leading Test and Measurement Tools. UEi Test Instruments are sold throughout North America and Canada and professionals recognize the UEi brand for quality and innovative features designed to solve real-world problems. UEi's NIST-certification laboratory is compliant with ISO17025. UEi backs its products with dedicated technical support, service and repair teams.