The 1590K431 is the mid-size 1590K4 zinc enclosure, a 120 x 94 x 56 mm box with a four-screw lid. It is a high impact zinc diecast alloy electronic instrument enclosure supplied in a natural finish, intended for OEM engineers and product designers who want a heavier alternative to Hammond's 1590 diecast aluminum enclosures.

Box and lid are made from diecast zinc alloy. Zinc is tough yet easy to machine and makes it easy to plate the enclosure. It feels cool to the touch and adds perceived premium quality weight to the finished product. The enclosure is vibra finished for a smooth surface with no sharp edges.

The ordering table lists 4.72 in (120 mm) long, 3.70 in (94 mm) wide and 2.20 in (56 mm) deep, while the part page gives 4.72 in x 3.7 in x 2.05 in (120 mm x 94 mm x 52 mm). From the drawing: inside height 52.30 mm [2.059 in]. Maximum PC board size is 87.3 x 113.3 mm, and a side wall draft angle of 2° or less simplifies PC board mounting.

Lap joint construction protects against dust and splashing water, and the enclosure is designed to meet IP54. Four M3.5 x 0.6 x 12 mm stainless steel Philips head machine screws secure the lid into factory tapped holes, with a recommended torque of 50-55 cN.m [71-78 ozf.in]. Plated replacement screws are 1550MS100 (M3.5 x 12 mm, pack of 100). The 1590K431 is RoHS and REACH compliant, ships shrink wrapped at 1.15 lbs (0.52 kg), and can be factory modified by milling, drilling or printing; solid models are available in .stp or .x_t.