The TAWATEC pen was designed to be the toughest pen out there, period. It is built to withstand blistering cold, intense heat and any kind of harsh environment an operator is bound to encounter. The thixotropic ink in the hermetically sealed cartridge and pressurized to nearly 35 psi lasts three times longer than a standard ballpoint pen. With an estimated shelf life of 100 years, the pen writes at altitudes up to 12,500 feet where most other pens simply won't. Best of all, no matter how harsh the conditions your TAWATEC Tactical Pen will work with operating temperatures from -30 to 250 degrees Fahrenheit (-35 to 120 degrees Celsius). Designed with a sharp as well as rounded end, it can effectively be used as a take anywhere defensive implement or control device. The smoothly finished point also doubles as a PDA stylus device. The external knurling and slightly upward tipped spring steel clip allow an exceptionally low slip grip while not snagging during deployment or holstering. The Mil-A-8625 "F" black anodizing over a non-marking finish provides a rock hard surface finish. The TAWATEC Tactical pen is made in the U.S.A. In addition, this pen also has a new and improved satin finish and non-reflective / non-marking surface treatment which helps minimize fingerprint marks and reflection off the pen. This pen fits into virtually any shirt pocket. Specifications ----------------- Length: 5.75 inches Thickness: 0.5 Inches Weight: 1.2 oz. Color: Black Material: 6061-T6 Aerospace Grade Aluminum Clip: Cold Pressed Spring Steel with non-reflective black oxide finish Finish: Proprietary non-reflective / non-marking surface treatment and Hard anodized to Mil-A-8625 "F" specifications Fittings: Black oxide stainless steel bolts and chemical welding Cartridge: Foray #877294 / Fisher #SPR4