ReThinc Refillable Dry Erase Markers are different from the old guard of whiteboard pens. Each marker contains an ink tank instead of a felt wick, so more ink is available and the pen lasts longer until the very end. Felt wicks gradually dry out as you use them. You can see them dying, but you hang on, trying to squeeze out all the possible ink. The vibrant color just dwindles away and it's finally is time to pitch the pen, body and all. Unfortunately, for power users, that can mean a lot of waste.
ReThinc Refillable Dry Erase Markers come pre-loaded with an ink tank, ready to go...after it's primed. Priming the pen takes about thirty seconds, breaking the tank's seal and starting the flow of ink. Just depress the nib on a hard surface and shake (the pen, not yourself) to get the ink to flow into the pen nib.
Once the flow of ink starts, you may occasionally need to shake the pen a little during use to keep the nib saturated with ink. When the nib is tilted upward, the ink in the tube naturally flows toward the back of the pen due to gravity. Just get its beak wet again and you're ready to roll.
A word of caution: Before changing an ink tube, make sure the one in use is completely dead. Pulling out a tube with ink that remains could cause a splatter. You'll know when you have a dry ink well; these pens are good to the last drop.