Power chucks needed to be greased on a regular basis to keep the mechanical operation of the chuck effective. Chucks that are not greased run the risk of having less clamping force and therefore allowing the work piece to slip or even fly out of the chuck. Thame Workholding stock and sell grease especially formulated for use in power chucks. It is available in either 5kilo containers or 12oz cartridges. Grease guns to apply the grease are also available.