It's fairly simple. For the extra pens please add additional pledge amount to any of the "PEN" pledge/reward levels. For the extra balls please add additional pledge amount to any of the "BALL" pledge/reward levels.
Please check the "Pledge Tips" section on the campaign page for more details.
To replace the refill in the pen, all you do is 1) pull the pen apart from the mid section, 2) untwist the twist mechanism, 3) replace the refill 4) twist back the twist mechanism and reconnect the two ends(you may need to adjust a little to make sure the scales are in the right place) and it's done!
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