The 1551CBK is the largest of the three 1551MINI subminiature enclosure sizes, molded in black ABS and measuring 65 mm x 30 mm x 15 mm (2.56 in x 1.18 in x 0.61 in). It is designed for dongles and small printed circuit boards with USB connectors, and its extra length suits slightly larger boards.

The box uses general purpose ABS in black (RAL 9011) with a satin texture finish and a UL94 HB flammability rating, and is designed to meet IP54. The cover is recessed 0.50 mm [0.02 in] for easy label installation.

The maximum PC board size is 25.5 mm x 59 mm. Molded standoffs accept #2 x 3/16" self-tapping screws, which are not included (order 1553WTS100, pack of 100). Two black #2 x 1/2" self-tapping lid screws are supplied, with a recommended torque of 35-43 ozf.in (25-30 cN.m).

The 1551CBK is RoHS and REACH compliant, packed in a bag, with a listed shipping weight of 0.03 lbs (0.01 kg). Replacement black lid screws are 1551USB50BK (pack of 50). The 1551USB3 series is this size with a USB-A male connector cutout. Factory modification (milling, drilling, printing) is available, and solid models can be had in .stp or .x_t format. As with any ABS enclosure, avoid acetone, ketones, thread-locking compounds, cutting fluids and strong solvents, which can damage the plastic.