Shorty Ballpoint Pen / Wörther

This is a Shorty Ballpoint Pen by Wörther, based in Baden Baden, Germany. It is a short hexagonal barrel ballpoint pen, made of plastic and has a retro feel to it. 
The pen is very compact, it sort of looks like a Kaweco's 80's version, and would fit in your pocket easily. 

Each pen comes with a D1 blue ink.
You can change a refill by unscrewing the tip, removing the spring, pressing push-button while pulling the refill out. 
Insert a new refill until it stops, release push-button, put back the spring and the screw. 
D1 refill in black available here

Dimension: φ0.5” x (L)4" 
Made in Germany