OK, this is not your normal review. Firstly, because I already had an idea of the strength of this flavouring and secondly it has been done in reverse. First, I must explain my methodology. I have used a fully charged 17650 battery in a Mako Maxi. I have used a new and clean LR 510 atty for each test so there is no contamination. Secondly, I have started in reverse, ie, I placed 1 ml of pure 36mg ejuice into a NEW container, uncontaminated by any other juices. Now I inserted 5 ml of HC RY4 flavour from a 110ml bottle I purchased myself. So, now we have 5ml of HC RY4 and 1ml of clear 36mg clear ejuice. Result No. 1 - at this feeble strength, which is 16.67% eliquid to 83.33% RY4 flavouring liquid. OK, I don't have to test any further because even at 1/6 of ejuice to 5/6 pure HC RY4 tobacco flavour, there is no tobacco taste whatsoever. I didn't bother trying any other strengths because this result was so disappointing that there was no use to try any more ejuice as even at this large quantity of flavour gave less than expected from five times as much of flavouring compared to one times eliquid. So, my opinion based on this one test (I was truly hoping to add more ejuice, but it just wasn't on) is that there is no way I can recommend HC RY4 flavouring because it is just too weak to add any flavour to even a 5:1 mix, which is ridiculous when you consider it should be the other way around ie 1:5 mix. OK, my next review will be with the 110ml of Flavor Flue cured tobacco flavouring, which I haven't tried yet. To be honest, I don't hold out any hopes of it being much better, but I would be more than happy to be proved wrong. I hope this review helps people to make an informed choice when ordering tobacco flavourings, in the end, I have to give this product 0 out of 10 because it has bugger all flavour when added to anything. I'm sorry to have to give such a poor review but I have to tell the truth as it is for me. If someone else has tried this flavouring and has a different view, I am more than happy to hear from them. Edit: I will be doing the same review on the Flue Cured Flavouring next, but to be honest, I don't hold out much hope for it to be any different than the RY4, I hope I am wrong, but I doubt it.