These really are one of the best Clarinet swabs money can buy. One pass through the clarinet is will generally do the job. However, buyers beware, if you go into a store you may be able to choose your colour. If buying on line, it tends to be a random choice. That random choice tends to be the colour the shop is left with. For some reason, that is normally green. I tried a number of shops to get one that was not green, but ended up adding this to a larger order. Sure enough, it was green. They come in about five different colours. UK, Germany and America always get left with the green ones.