I think the plexiglass ones are someone else. Jeff's site only lists wood and buffalo horn versions.

This combo device is a neat idea. Hopefully I can do a handdrill fire too.

I practiced with the piston last night and I found that the choice of tinder fungus made all the difference. My pieces of fungus have both a hard outer bit and a punky inner. I get a glow and coal with one whack of the piston if I choose a punky bit of fungus. It glows and holds heat for a long time with just the small piece that fits in the piston well. The harder crusty fungus pieces do not light as easily for me.

I did not build any fires last night, just produced about 10 coals.

This is a very nice piston and even though I had whacked it about 25+ times it was still comfortable to use. I tried the Jeff Wagner crunch and the high velocity hand whack....both worked and right now I cannot say which I found easier...selection of fungus seems to be the most important aspect.

I brought my tin of char in today to see what else I can smoke at my desk

I like this device, and it was quite a good bargain.