Model IDs

A model id is the string Logitech's own tooling uses to name a product. OpenLogi keys per-device configuration by it, and resolves a device's render and hotspot metadata with it on assets.openlogi.org.

What the id is made of

A device reports its identity through 0x0003 deviceInformation: up to three model_id PIDs — one per transport the firmware flags (USB, eQuad, BTLE, Bluetooth) — and a one-byte extended_model_id, a production-line attribute such as the colour run. openlogi list prints both under each paired device:

     model_ids=[b042,0000,0000] ext=02 serial=— unit_id=00010203 transports=usb+equad

The registry's id is the two joined, extended byte first:

model id = {extended_model_id:x}{model_id[0]:04x}

So ext=02 and model_ids=[b042,…] give 2b042.

Four-digit ids are a bare PID — depots that predate the extended byte, and everything the registry identifies by USB PID alone: receivers (c548), webcams (085e), G-series audio (0a9b).

Trust the last four digits

The leading digit is Logitech's registry convention, not a reading of the device, and the two drift apart in the field: an MX Master 4 is listed as 2b042 while the unit reports ext=01. A product also answers to a different PID on each transport — an MX Master 3S reports b034 over Bluetooth LE and b043 through a receiver, and the registry lists both.

OpenLogi matches accordingly: the full ext + pid string first, then the trailing PID alone, and only then a bridge from the firmware codename to the registry's display name. Search this index the same way — by the four digits your device reports, not by the prefix.

The index

Every model id the registry lists, one row each: a product that answers to several appears once per id, because the id is what you arrive with.

The same rows are served as JSON at /model-ids.json — { id, name, kind, depot } each, in the same order — for scripts, and for anything that would rather not scrape a table. depot is the directory the device's assets live in under assets.openlogi.org.

Where the index stops

• The registry is the source. These are the products Logi Options+ ships assets for. Gear that only G HUB drives, and devices from before Options+, are not listed — their ids are real, they are simply not here.
• Only the ids the registry lists. A device reports up to three PIDs but most depots publish one, so the id you hold may be a transport this index never names for that product. That is what the trailing-PID search is for.
• A receiver appears as a product, under the USB PID it is identified by. How OpenLogi talks to one is Receivers.
• Presence is not support, and absence is not a verdict. OpenLogi opens any Logitech HID interface that carries an HID++ vendor collection, so a device that is missing here can still be driven — while the headsets and microphones that are here are not configured by OpenLogi at all. What each product exposes is on Supported devices.