A vee block (or V-block) is a square or rectangular precision-made block used to securely hold a cylindrical workpiece on a milling machine or drill press.
They are called vee blocks because they have at least one centrally located v-shaped groove upon which parts are positioned.The groove is parallel to both the sides and base of the block so that parts are correctly centred and ready to be machined.
Vee blocks can be used to hold work either horizontally or vertically.
Because long cylindrical parts may require more than one block, vee blocks usually come in matched pairs.
However, sets made up of blocks of a number of different sizes, are also available.
They are supplied with clamps so that parts can be fastened firmly to the vee blocks.