The 50 Caliber Cartridge Rollerball Flip Pen is made from an actually fired 50 caliber cartridge. The shell is the stand or holder which sits on your desk. To use, just pull the pen out of the shell and start writing with this rollerball pen. It's a total of 5 1/2 inches long. The shell is 4 3/4 long and the pen is 4 3/4 inches long and is made of walnut.