Pioneering in technology the trekker Space Pen can hang upside down forever yet function immediately when needed. This pen is "the Bomb" for so many different folks. Are you an executive? Put it on your keychain and always have a quality writing instrument at hand. Police/Fire/Ambulance...clip it to your belt and it will sail through the daily abuse it will get! Students love this on their school lanyard. It's the choice of mountain climbers, sojourners, farmers, and security guards. Give this pen as a gift and you'll be remembered forever.The trekker Space Pen with a key chain ring attached to the posi-lock cap allows for easy accessibility. The trekker Space Pen comes with a carabiner and a break-away lanyard making it easily attachable to a belt loop, back pack, purse, climbing gear, briefcase or anything else that is within your reach. VERSATILECOMFORTABLEFUNCTIONALStyle:Snap Off Cap Length: 3.875" x .375" diameterRefill: Fisher PR4 Pressurized Refill. Black Ink. Medium Point.Composition: Stainless Steel with Fisher Rubber Comfort GripPackaging: Clam Shell