What the 398800302 is
The Molex 398800302 is a 2-position, single-level Eurostyle 39880 barrier terminal block with a 0.200 in (5.08 mm) pitch. It terminates 16–30 AWG wire via a screw rising cage clamp — the clamp body is nickel-plated copper alloy; the contact is tin-plated copper alloy. Rated 13.5 A per circuit and 300 V, the housing is PA66 (nylon 6/6) in black, mounts horizontally through-hole on a PCB, and operates from -40°C to 105°C. The side interlocking feature lets you gang multiple blocks into a multi-circuit rail without separate mounting hardware.
Where barrier terminal blocks like this are used
Barrier terminal blocks in this form factor are the field-termination point for power distribution and control wiring inside industrial enclosures — you see them on the input side of drives, contactors, and instrumentation racks. The rising cage clamp is the go-to in factory-floor panels because it accepts a wire without a ferrule and releases it without spring fatigue, which matters in hard-wired installations. The interlocking side feature on the 398800302 is what lets a panel builder assemble a multi-circuit rail from multiple 39880 blocks without drilling separate panel holes for each one — a real labour saving at higher circuit counts.