
Left: 19th Century. Halifax County, VA. Yellow pine. Cuttlery or small tool tray. Handle is re-used 18th Century thumb latch. Cut-nails throughout; reinforced over the years with some round nails. Center divider runs the length of the box.
Center: Late 19th Century. Halifax County, VA. Yellow pine. Primitive center handled carrier/box. Wood has been re-used; round nails throughout.
Right: Late 19th Century. Halifax County, VA. Yellow pine. Primitive carrier with 3 compartments. Round and cut nails.

19th Century. Southern. Yellow pine. Large tool tray. Cut-nails throughout; reinforced over the years with some round nails. Original green paint with nice wear and wonderful patina.
Source.
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Large tool set
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A tool play set, 1910.
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Small vintage Mahogany tool box. 30" wide, 8 3/4" high and 6 1/4" deep.
Source. 

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If this is something he takes with him on his travels, I'd think it would close or have some sort of lid on it. Something to make sure the tools don't fall out. But a design that can be easily accessed, one that we can see what's inside is also important.