The 1591HBU is the blue colour version of the 1591H size in the 1591 Series of ABS plastic multipurpose enclosures with card guides. At 6.52 x 2.79 x 1.14 in (166 x 71 x 29 mm) it is a slim box and lid for product designers and engineers who want a coloured housing that stands out from standard black or gray.

The 1591H drawing lists this blue part in FR ABS rated UL94 V-0, and the part page confirms ABS plastic with a UL94 V-0 flame rating and an IP54 ingress rating. Lap joint construction guards against dust and splashing water. Because some chemicals can damage or weaken plastic, avoid acetone, ketones, strong solvents, thread locking compounds and cutting fluid when working on it.

Card guides molded into all side walls accept 1.5 mm (0.062") boards for vertical PCB mounting; the guides are 20.00 mm [.788 in] tall. Usable interior space is 159.70 x 64.80 x 25.00 mm [6.287 x 2.551 x .984 in]. The optional 1591Z card adaptors let you mount boards horizontally instead.

The 1591HBU assembly includes box, lid, 6 cover screws and pre-installed brass inserts that accept M3 - 0.5 machine screws; tighten to 35.5-42.5 ozf.in (25-30 cN.m). It is RoHS and REACH compliant, ships in shrink wrap at 0.22 lbs (0.10 kg), and can be factory modified by milling, drilling or printing.