These are sturdy ABS clam shell plastic boxes that snap together very securely. The clam-shell halves of the box are identical and mate with each other. We stock two sizes and either size may be used to form boxes with the same size clam shell or the with the other size. Wall thickness on the sides seem to vary between .070 and .080 depending on the place I measure them.

The two size clam shells are 

Inside Dimensions -  one half
4.7 x 2.6 x .49 - small size half
4.7 x 2.6 x .93 - large size half

Inside Dimensions - box (two halves)
4.7 x 2.6 x .98 - small size box
4.7 x 2.6 x 1.86 - large size half
4.7 x 2.6 x 1.42 - one small and one large half

Outside Dimensions one half
4.88 x 2.77 x .58 - small size half
4.88 x 2.77 x 1.025 - large size half

Outside Dimensions - box (two halves)
4.88 x 2.77 x 1.16 - small size box
4.88 x 2.77 x 2.05 - large size box
4.88 x 2.77 x 1.60 - one small and one large half

The larger box half has standoffs that measure .33" and .57" from the bottom of the box - or the top. They are easily removed or modified with flush cutters.

The larger half also mates with the smaller half - we think you can do the math on the dimensions. 

Sold in halves - so you can mix and match. Hint - don't order just one unless you want to store hardware, or resistors, in it.