I design this pencil case to carry every day my fragile rotting 600, this pencil fits perfectly in this case. I use 8 neodymium round magnet: 5x3mm but you can also use 5X4; if you use 5X3 I recommend to not push it far back in the plastic because the pencil case close not as well, also test the magnet polarity before to push the magnet in the print usually they don't need any type of glue but you can add it if you want, also don't use extreme heat because magnet can broke or demagnetise itself.
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