The internal hooking solution. JM-1, JM-2, and JM-3 Buy industrial hooks specially made from stainless steel flat stock, able to maintain tension even after repeated stripping. Four sharp corners bite into the tube walls for greater holding power. Request a sample to try our superior design. JM-4 and JM-5These industrial metal hooks for automated lines are manufactured in 0.105" diameter hard drawn wire. The design allows for easy loading and unloading without squeezing the hook. The extra bend on the JM-4A and JM-5A provide extra tension that will allow their use in a variety of tubing sizes. Special jam hooks have been made in lengths up to 60". Custom hooks can be manufactured for heavier and larger tubing or for internal hanging of awkward and complex parts.