GearWrench Insert Bit Set, Metric, 8 Piece, Specifications Met: ASME Specified, for Use With: 6 and 12-Point Wrenches or Ratcheting Wrenches, Zinc Phosphate. GearWrench ratcheting wrench insert bits are designed to give excellent access in tight places. The insert bits fit into the box end of a wrench, performing like a bit socket on a ratchet. The advantage of insert bits over ratchets and bit sockets is that they have a lower profile and are not as wide, providing greater access in confined spaces.