One thing I have added to my kits is a small, packable backpack. I attach it if there is not room in the PSK container. My PSKs are so tightly packed that once you pull things out, it is tough to get it all back in. I use the Kiva Keychain backpack, and they come in various colors. My kids' PSKs have orange Kivas. The backpack also aids in collecting useful materials or foraging for edibles. I have recently acquired a Sea to Summit keychain back pack which is just as small packed as the Kiva, but holds a bit more and is more durable.