jodi_maloneyThis pen will take any parker style refill, though you may have to trim the refill, to fit (or use the included tubing as a spacer, for refills that are too short).
The EnerGel is the right shape, but it's a little long. You will need to trim it to fit.
The P8126 adn P8127 refills are the exact same size, just different size tips (0.6mm and 0.7mm)
The Retro 51 Tornado refill is a rebranded Schmidt P8127
And for those who complain about the refill being "evil", that liquid ink is what makes it such a loved and silky smooth writer. But it also makes it prone to bleeding out, if the tip is exposed and touches your pocket. If you want to go in the other extreme, the Fisher Space Pen refill is a parker style compatible refill. That would make this the ultimate EDC pen!