Enchantability is a stat that determines the odds of getting a good enchantment, as well as how often you get more than one on an enchanting table. The shield's enchantability isn't documented in the wiki, so I think it would be a good idea to document it for more technical players.

More technical players could just look for it in the Java files, there is not really a good place with how I structure documentation for the mod to put it on the wiki, its a very non-technical wiki.

Your best bet is really getting a mod that lists that sort of info if you want it, since its hidden on all vanilla and modded tools anyways.

Anyways, its enchantability is 12, or 16 if it has a pattern.