please would you clrify what you mean by "small to medium" and "medium to large" candles? (ie Diameter would be useful!) Thank you for your help.

The Candle wick we sell refers to the diameter of the finished candle so the 'Wick 6mts 38mm' means your finished candle would be about 38mm in diameter. This is a rough guideline you could be about 25mm either way and you won't notice a massive difference. If the wick is to big your candle will burn a little bit to fast and smoke a bit, too small and it will burn slower and tend to go out easily.

for further reading on selecting your wick size please follow this link

http://candleandsoap.about.com/od/tipsandtechniques/qt/qtwicktest.htm