
This is a solid box but the "internal size" given is the maximum size and doesn't include the screw gussets so I couldn't use it for the project I was making bought for. The size I bought was listed as "Internal Dimensions: 224 x 144 x 82mm / 8.8" x 5.7" x 3.2" (L*W*H)" but the usable width was closer to 4.7" since the rebar is about 1/2" up each side and was only about 8" long.

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