The kit comes with a box of (6) Shatter Bait Cartridges. Not all of the Hex Pro Stations will need bait. Typically, only a few Hex Pro Stations will get termite "hits" and need have Shatter installed. 6 Shatter cartridges is enough bait to kill an average size subterranean termite colony. Basically, when the Shatter cartridge is nearly empty, we recommend to replace it with a new cartridge. In most cases, Shatter cartridges never need to be replaced once installed.