The 1N6130AUS: It is a single-channel device in a surface-mount SQ-MELF B package, built for general-purpose circuit protection.
At 500 W peak pulse power, this part can absorb a transient that would fry a lower-rated part. The 137.6 V clamp at 3.6 A means a bus sees a hard ceiling during a surge — the downstream regulator or capacitor only needs to survive that peak, not the raw transient. Bidirectional design (single channel) means it clamps both polarities, so you can use it on AC signal lines or bipolar DC rails without worrying about orientation.
Active production — no lifecycle risk for the BOM
That means you can plan multi-year builds without a last-time-buy scramble.
Package and mounting — SQ-MELF B in surface mount
The SQ-MELF B (B, SQ-MELF) is a surface-mount package with a cylindrical body and metalized end caps — it reflows like a standard SMD but needs good solder paste volume on the end caps for a reliable fillet. No power line protection built in; this is a transient suppressor, not a filter.