Survival kit part 4 the knife

Now a survival knife should ideally be a full tang (that means the blade continues all the way into the handle for strength) with a blade big and solid enough for light chopping (branches etc) it should be easy to sharpen but not too brittle.  And there's the problem, try carrying that around every day here in the UK and you'll soon be helping Mr Plod with his enquiries.
 Long gone are the days boy scouts walked around with a good old fashioned sheath knife on their belt.
 The law in the UK is complicated and confusing, but basically what it says is to carry all the time legally the knife must have a folding blade under 3 inches long (about 7,5cm) it can't be a locking knife either.  Which is a big problem, because finding a non-locking knife with a 3 inch blade is like looking for rocking horse dropping, bloody difficult!   For some reason despite the law here in the UK almost all the small knives on sale are locking knives. The reason for this is simply they are safer as they wont close on your fingers.
 So whats the solution?  Well you might get lucky and find a small suitable pen knife (I did cheaply off Amazon) the other options is a small cheap multi-tool, I've seen these is places as varies as camping shops to radio shack, although do check it's non-locking, many are.  For true quality if your not on a budget (and not in place with silly laws) you could buy a Gerber or Leather man,  both superb quality, but sadly both locking.
 You can technically carry a locking blade knife or multi-tool, but the law says you must have a good valid reason for carrying it in a public place, unfortunately it's left up pretty much to the individually policeman (or woman) to decide whats valid. My advice is try to stay withing the law for everyday carry, but if your off out into the wilderness consider taking something bigger.
 My personal favorite for a sheath knife is the good old US air force survival knife, these have about a 5 inch blade and a sharpening stone for keeping the blade sharp.  I don't know if they are still available, I've had mine since the 1970's, built like a tank and plenty sharp enough, solid enough for light chopping too, curiously they used to come with a horrid beige sheath ( I stained mine black), and at one time there was allegedly a spear handle to screw onto the blade, although I never heard of anyone actually having one.
 As for the survival tin, if you cant find a small penknife get a few Stanly knife blades (dead cheap) or some of those one sided razor blade things that craft shops sell and fold them into a sheet of paper and put them in your kit, not ideal but at least  you'll be able to cut stuff.