Fine feed for mill/drill head PF 230 and micro milling machine FF 230 Easily installed. The feed may now be used via the height feed (vertical) or the fine feed in the tilted position. One revolution is equivalent to 1/16" (1.5 mm) spindle travel, with 1 division = .002" (0.05 mm). The graduated scale can be reset to zero.Proxxon tools come with a 2 year factory warranty.