Since the demise of Maplins, I have not found a UK source for "Magic Smoke." I did find "Magican" online from a supplier in Germany and now have that to hand. Yes, it arrived very quickly but the carriage was nearly the cost of the can at ?17 in total. Has anyone found a similiar product in the UK ?

https://www.ebay.co.uk/itm/Magican-Hazecan-Fog-in-a-Can-Smoke-Portable-Machine-Aerosol-Haze-Effect/172916826891?epid=1763366831&hash=item2842a5630b:g:lNEAAOSwQItT9Hto

What do you use it for?
I am trying to locate on the surface second entrance to a very drafty cave and one option was to use smoke and try to find where it come out back to the surface.
Can this kind of smoke hurt the cave in any way? 

Just take someone who vaped with you, they seem to emit large clouds of smelly media at regular intervals

I buy ours from Stage Electrics. It is the same as suggested by SamT but cheaper. You may find it better to bulk buy to save carriage costs.

https://www.flickr.com/photos/11409438@N06/31104150477/in/album-72157679947221496/

A can lasts a long time if used carefully. When prospecting at surface I use split second bursts and follow up anything interesting with a one to two second burst. The "smoke" is, I understand, olive oil or something similar, so it is best not used near naked flames. It is neutrally bouyant so hangs well in the air, this gives it an advantage over cigars, joss sticks and burning tyres etc. The mass emitted when spraying is very small and used carefully the environmental effect is negligible, I test sprayed a heavy overdose on surface rocks, so that the rocks looked wet and shiny, but six months later there was no trace and no vegetation change.

Here is the url for Stage Electrics - the boss knows he sells some cans to cave diggers.
https://www.stage-electrics.co.uk/shop/sales/special-effects/fog-smoke-flame-and-haze/aerosol-sprays/product.aspx?code=755-5899&nr=true

.

I remember Steve Round in Bernies once having a good laugh as he told us the story of some cavers using canned smoke to find a surface connection on a day with very thick fog...

Maplins are still trading, on-line only...

https://www.maplin.co.uk/

Thanks folks. We are in a draughty dig but need to know its precise origin. Will try it out tomorrow.