The 1550Z108 is a natural (unpainted) thick-wall diecast aluminum enclosure in the Hammond 1550Z watertight series. It shares the nominal 125 x 80 mm footprint of the 1550Z107 but steps up to a 59 mm total depth, giving roughly 50.80 mm of inside depth for taller components, terminal blocks or stacked boards while keeping the same compact plan size.

Overall dimensions per the drawing are 125.40 mm [4.94 in] long, 80.40 mm [3.17 in] wide and 58.80 mm [2.31 in] high, with inside dimensions of 116.04 mm [4.57 in] (length), 70.64 mm [2.78 in] (width) and 50.80 mm [2.00 in] (depth). The listed maximum P.C. board dimensions are 70.14 mm and 115.14 mm, and the lid height is 0.63 in (16 mm). Shipping weight is 1.05 lbs (0.48 kg).

Box and lid are made from diecast aluminum alloy that is tough yet easy to machine, and the walls have no internal ribs, so connectors fit without interference or extra milling. This unpainted version is vibra finished for a smooth natural aluminum surface with no sharp edges, and the alloy is easy to machine for custom openings.

The purchased assembly includes the box, lid, silicone gasket and 4 stainless steel Phillips head cover screws, which sit outside the gasket protection area so no o-rings are needed. On this size the lid screws are self-captivating: the lid holes are slightly undersized and are threaded with the first installation, so the screws stay with the lid when it is removed. Recommended cover screw torque is 5-7.5 lbf.in (50-75 cN.m). For wall mounting, the box uses blind thru-box holes located outside the gasket ring, so access to them does not compromise ingress protection. An internal ground point accepts an M4-0.7 machine screw; matching hardware is sold separately as SCGM4-50.

The 1550Z series is cUL and UL listed (file #E71073) and independently tested to IP66, IP67, IP68 and NEMA Type 4, 4X, 12 and 13; this size is rated IK08 per IEC62262. It is RoHS and REACH compliant; customers should test suitability for their specific application.