In addition to a plug tool and kit, I carry one of those compressed cans of "Fix-a-Flat" or whatever it's called. It forces sealant into the the hole, if it's a small enough one and pumps up the tire at the sametime. Good enough to get you to a shop or service station, etc.. Heck, you're gonna end up throwing the tire away anyway and getting a new one so no biggie with that sealant in there.