The 35-310 AB is a Best A section blank, so it only fits cylinders and cores cut to the Best A keyway. That is the most common small format interchangeable core keyway in commercial buildings, and if your cores are A keyway this is the blank a locksmith cuts your keys from. Put it in front of a different keyway and it will not enter the plug.

No. Best keyway sections are not interchangeable, so a B, C, D or other section core will not accept an A section key. Order blanks in the same letter section as the cores on your doors, or you will end up with a box of keys that will not enter a single cylinder.

It ships as a blank, uncut. A locksmith or your in-house shop cuts it to your existing key bitting or to a new keying schedule. The same applies to the un-combinated small format cores ZenSupply sells, like the GMS 6-Pin Small Format IC Core, which ship without keys, pins or springs and get keyed at the same time.

The embossed "DO NOT DUPLICATE" marking is a deterrent, not a lock. It tells a key counter or hardware store that the holder is not authorized to copy the key, and most reputable shops honor it, but it carries no legal force and a machine will still cut it. If you need copying genuinely controlled, that is a patented restricted keyway with key control cards, not a stamped blank. For most property managers issuing tenant or staff keys, the stamp does the job of cutting down casual duplication at the corner store.

Keyway is the one thing to get right. The 35-310 AB is ordered under keyway S123, the Best A section. Match that to the section stamped on your existing cores or on the bow of the key you are copying, and confirm your keying schedule (master, grand master, or change keys) before the blanks go to the cutter.

Yes, and plan for both. Small format interchangeable cores such as the GMS 6-pin and 7-pin cores are sold un-combinated with no keys, pins, springs or caps, so blanks like the 35-310 AB are a separate line on the order. Count two keys per core minimum for change keys, plus your control and master keys, and make sure the pin count on the core matches what your keying schedule was built around.