Newly redesigned and released in December 2015! Designed for the TWSBI Vac 700 and the Vac Mini fountain pens, this TWSBI Vac 20A bottle with Blue cap allows for a complete full in one stroke. Simply fill the bottle with ink, screw the TWSBI Vac fountain pen into the top of the bottle, extend the vac plunger invert and push in the plunger to fill completely. The new design also now works with any fountain pen by unscrewing the upper cap. The Vac 20A bottle parts are not interchangeable with the older Vac 20 bottle parts.