The Tombow Airpress is an ingenious and fascinating pressurised design ideal for a multitude of uses. Writes upside-down or on dusty or wet paper, thanks to the refill which is pressurised every time you click the pen to extend the tip. Chunky elastomer barrel is easy to grip in cold or wet conditions; big strong wire pocket clip pivots out nearly 90 degrees to attach firmly to just about anything; and there's a useful loop on the top of the barrel to let you attach the pen to a lanyard or keyring.

The refill is normally unpressurised, but when the button is pressed to extend the tip, the internal mechanism is primed with enough high-pressure air to power the refill for up to 150m of writing. A window in the barrel shows the patented piston at work - a pen with great 'fiddle-factor'. Compact but easy-to-handle design is approx 12cm long and 12mm diameter.

Fine ballpoint refill contains black waterproof ink. Refill with Tombow BR-SF refill.