Jindeng products quality trustworthy! The cooperation with kingden was introduced by a friend. However, the combination screw is composed of a screw and a pincushion. Fasteners that are combined together by threads. The combination screw is easy to use, do not hand-match bolt, cushion, flat mat. So it's more convenient. But the price is a little bit more than the single bolt, the cushion, the pad add up. Teaching you how to choose the combination screw & NBSP; Combination screw function: has perfect binding line pressing ability, is supporting the high and low voltage, high and low pressure air conditioning connection, contact is current of electrical voltage, power, frequency, power performance significantly improved compared with the traditional separation of screw, can save people, save work, time saving, etc. The products are applicable to all kinds of electrical equipment. Electrical appliances, equipment, communication equipment and other mechanical equipment.