So called because they use eight conical white rubber buttons to grip the work and pull it securely back against the aluminium jaw plates without damaging the edge. Although the rubber buttons are easy on the wood they are not really suitable for bowls with a very fine edge, these are better held in specially made wooden jaws mounted on the Axminster wood jaw plates. As well as the tapped holes there is a slot provided in each of the 250mm jaws (not the 400mm ones) which allows the position of the jaws to be finely adjusted to accommodate slightly irregular pieces. Two sizes of plate are available, one for bowls up to 225mm diameter, the other for up to 400mm. As an alternative to using the buttons, stacking turn studs are available as an optional extra. These are designed as a primary holding device for all manner of round or square blanks and giving a very secure holding method, they can be used singularly or doubled up using the longer bolts supplied. Both sets of jaws are supplied complete with buttons, with spare buttons available individually or as a set. N.B. The 400mm jaws are not suitable for use with the Axminster AWVSL900 and AWVSL1000 lathes.