Kaweco Sport Rollerball Pen Classic - White
The Kaweco Sport is my go-to pen, hands down.
Capped, the pen measures 10.5 cm and fits easily in your pocket. Once you put the cap on the back (or post the cap if you want to get geeky), it extends to a comfortable full size pen.
Color - White with gold details
Material - Plastic
Cartridge - Black .7