A few of mine I use the most........ But I like to go on a walk with a piece of char and one of the following tools and create a fire. Call it a personal challenge, the rock to toss sparks has to be found while on my walk. The knives are pretty easy ,with the low R.C. of the ESEE posing the most challenge. Until I got some help from @mauiarcher [Thanks Again] That opened the door for more testing. The Axe is the hardest and almost worthless, 8-10 strikes for 4-8 weak sparks. But it is possible. The one Striker missing that I use a lot is a small piece of Carbon Steel Hacksaw blade carried in my wallet.