With the exception of the Birtcher 71, all other Calmark/Birtcher extractors, including the Calmark 107 nylon extractor, are specifically designed for sheet metal applications. To be compatible, the design engineer must incorporate a U-channel in the card cage for the “head” to push against when inserting or ejecting the PCB. Nylon inserters/extractors are ideal for applications that require up to 100 lbs of force. The 107 inserter/extractor offered through DigiKey has a mechanical advantage of 4.5:1, supports a board thickness of 1.6 (.063”), is made of glass filled (30%) 6/6 or Type 6 nylon, and has a UL94 rating of V0, which indicates the resistance to flame. V0 is the stricter of the two standards, and specifies that the unit must stop burning within ten seconds and drips of particles are allowed as long as they are not inflamed. All Calmark/Birtcher nylon inserters and extractors may be used at temperatures up to 250°F continuously and are resistant to alkalis, weak acids, and common solvents.