The 1555D2GY shares the 120 x 65 mm footprint of size C but with a taller 61 mm total height (nominal 4.72 x 2.56 x 2.40 in; the part page lists 4.7 x 2.6 x 2.4 in, or 119 x 66 x 61 mm). The extra depth suits taller components on narrow boards, for integrators and OEMs building outdoor or UL 508A listed assemblies.

As a polycarbonate 1555 enclosure it is cUL and UL 508A listed under file E65324 and independently tested to IP66, IP67, IP68 and NEMA Type 4, 4X, 6, 6P, 12 and 13. It is UV stabilized for outdoor use, rated UL94-5VA, has an IK08 impact rating per IEC 62262:2021, and is recommended for -40°C to +110°C (-40°F to +230°F).

Inside are threaded M3 integral brass inserts and/or standoffs for #6 self tapping screws, vertical card guides for 1.5 mm thick P.C. boards, and lid standoffs. Maximum board size is 52.83 x 110.49 mm. Like size C, size D has no internal DIN rail mounting tabs. The optional 1554CPL steel inner panel is shared with size C and fits in the box or lid.

Four included M4 stainless steel lid screws are self captivating and thread into corrosion resistant inserts; recommended torque is 43-57 ozf-in (30-40 cN-m). The tongue and groove lid seals on a one-piece silicone gasket supplied loose (replacement 1554CGASKET). Two 4.00 mm mounting holes are outside the gasket channel and accept the 1554FT foot kit. Shipping weight is 0.31 lbs (0.14 kg), shrink wrapped.