I just go to AC Moore and buy a few of those plastic 'Bead Caddies' when they have them at 1/2 price.
The boxes are 10.5 inches long by 7.25. They are divided into three rows of six, with two of the sections opened together for longer parts.
Normally costing $1.99, buying them at a $1 is rather cheap. I know they are available in a translucent pink or blue, but I prefer the clear versions.
I have about 13 of them, with a couple of empties
#1 Heads (each section can hold about 20 heads)
#2 Arms (each section holds about 20 pairs of arms)
#3 Legs w/waist (each section holds 6-8 sets of legs with o-ring, matching waists in adjacent section)
#4 Legs (each section holds 6-8 pirs of leg, no waist pieces though)
#5 Cobra Torsos (each section holds 6-8 torsos depending on size)
#6 GIJOE Torsos (each section 6-8 torsos depending on size)
#7 Waists/Thighs (each section holds 15+ waists or thighs)
#8 Misc Weapons/Helmets/Shields/etc (one section has Payload's rocket pack)
#9 Cast Parts (heads and torsos)
#10

Parts
#11 Feet/t-Hooks/New Sculpt Stuff/Modded Stuff/Unmatched Parts (missing, broken, no screws, etc)
#12 New Sculpt stuff/Broken Arms/Misc
#13 bbi weapons
I store my o-rings, screws, modded parts, painted stuff, etc in various boxes.
On my desk I have a few of the plastic inserts from the BTR vehicles. These are great for holding all the parts of a current project or as a catch-all for stuff going back into the other boxes.
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