Non-toxic, lead-free shot, made in the UK. Adding shot to a leader or tippet is far more common in the US than the UK, on some of our waters shot is banned, on a lot more it is a legitimate option which British fly fishers don't exploit. The idea is simple, rather than me tying nymphs in several weights, I carry one fly and add weight to the tippet. Of course, I can also use shot directly on patterns like a Peeping Caddis, or Leadhead.

The Stealth dispenser has 5 shot sizes, each size comes in four colours. The colour is a semi-matt coating, which colours the shot and helps protect my tippet from the metal weight. I like that I can use the colour to match the river-bed a little and the 'egg' shape looks good and at least makes me think these will be less prone to getting stuck than old, round shot.

I carry pliers anyway, so it's very easy to pinch these to a tippet; that coating also seems to help prevent the shot slipping on my leader. It's surprisingly easy to open these even when squeezed shut with pliers – the metal is a tin alloy, harder than lead, so less prone to being crushed.
I'm guessing the smaller sizes will prove handiest, the small shot are lighter than a similar sized tungsten bead and a fraction of the cost. Given the range of sizes here I can weight a leader quickly and much more exactly than I can using weighted flies – a flexible and economic option. Casting is no different than casting weighted flies, given weighted flies are on droppers casting and shot is on the main leader, casting may even be a little easier.

Well worth having a pack of these in your bag, for waters where shot is 'legit'; an inexpensive and highly adaptable means of weighting a leader, or fly.