This fully functional ink pens contains a concealed knife blade. Just twist the handle to extend the pen point of pull apart to reveal the 2.5 inch stainless steel blade. The blade is housed in a durable, aluminum pen casing and it is 5.625 inch in overall length. 4 ounces. Have that extra measure of self defense in hand. 2.5 inch concealed stainless steel blade. Durable aluminum pen casing. Contains black ink. 5.5 inch total length.