Nice simple block with some nice touches and a few minor issues. (see photo 1). The wall thickness of 3mm (eighths of an inch) makes it extremely durable. Two problems: (1) One of the mold's injection points is very close to an edge, making that point a little less effective as a seal (but caulk or butyl tape fills well). (2) The lack of instructions made me wonder where the gaskets should go on M20M fittings: inside or outside? When on the outside (as shown in the product photo), the seal will deform as it wraps around the shape of the box (see photo 2). Tightening the nut pulls it away from the threads on that side. Putting the gasket inside (Photo 3) seems to create a good seal, but now without the gasket the outer fitting has the ability to absorb water which can cause problems during freeze/thaw cycles. Again, a proactive application of sealants is a likely solution.