It’s maddening when Mitsubishi is inconsistent with its numbering system. Take this bunch for example…
The pencils are BOXY M5-300 (300 yen) but the matching ballpoint are BOXY-200 (200 yen, note the dash). This confuses the BP model with another BOXY series called BOXY 200 (without the dash). Oh well.
In any case both the MP and BP came in a similar array of bright colors. Truth be told, I’m not that keen to collect a full set of both. So instead I reserved Red, Blue and Black for the ballpoints (to match the refills eventually), while the pencils got the brighter Pink, Green and Yellow. I’m not 100% sure if there is a light blue model as well.
Lastly… the issue of ink refills. These pens (along with a couple other vintage Uni designs) require a super slim tip. My best bet was to use a hobby saw and trim off a current day Schneider Express 225. This particular modded refill will find its way into the other pens when I put them in rotation.