Hey, you've got two blasters too!! Haha!
Yeah, that hole is supposed to be there. There is this little clear rubbery plastic deal that goes on the bottom and then a spring clamp that holds it on. One of mine fell off at one point and I just duct taped it closed. It's there for cleaning and if water got in there, to drain it. I'd like to think that it's for cleaning!!! Every now and then when you want to clean the entire airbox out you can remove the plug, spray it down in there, and catch the junk coming out of the drain there.......OR, you could plumb a super trick ram air tub into it!!!! That would be a nice addition to KaleCo Auto's fine line of products!