It is basically a chinese air heater with a breakfast bar leg on it , inside the one I am using is 2.5m of 10mm copper pipe , the above pic is 5m , but it was to wide to go in the tube , so with a better sourced bit of tube later on the 5m will go in giving me more heat again .
The flow is probably better than before I cut the original heat sink body off , it appears to run as it was intended , but it does get quite warm in the van if shut up , even with the fan on the burner going !
Might have to have a rethink for summertime , but then I dont suppose I will need to run it then will I .