Tubing Connector Fittings, High Pressure, One Piece, 1/16th, PEEK, Natural, Large Combihead with 10-32 Screw Threads. Finger or wrench Tighten, ARE-Applied Research brand. These all PEEK tubing connector fittings are used to connect PEEK or Stainless Steel tubing in the high pressures zones of HPLC systems. This Combihead Fitting has a partially knurled, rounded head for hand tightening and a "Flat" section of the head for using a wrench for a final quarter turn or to loosen the nut when it is tightly screwed into the fitting. This fitting has 12 mm head, 22 mm total length (top to bottom) with an 8 mm thread length. The beveled inlet hole helps to make threading the tubing through the fitting easier.