At 40 mm in diameter, this will fit in even shallow toolbox drawers if you lay the keys flat as pictured. Even so, you never have one blocking the other like with the flat organizers!
Allen key sizes: 1.5, 2, 2.5, 3, 4, 4.5, 5, 5.5, 6, 7, 8, 10
The holes are designed for a slip fit and the o-ring is what holds them in. Use a 30 mm o-ring to hold them in nice and sturdy.
No supports needed.
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