The rattling is the removable saw blade.

I bought one as Costco. Love it. It's too heavy to carry when I hike long distances though. I'll take a lighter multi tool then. I carry it on my belt daily. Wouldn't buy at costco again, the knife that comes in the kit... it's not all that great. I threw it in the ash tray on the truck, just in case I forget mine one day. Haven't seen it in a couple of months.

Only complaint, the straight blade on the Surge...and the knife for that matter, are almost recurve blades because someone ground them poorly. Took me a good bit to get that fixed but now it's fine.