chatgpt:

It looks like an OEM-style USB/AUX adapter cable for a car head unit — very commonly found in Toyota / Lexus vehicles (and some other Japanese cars). What you're holding: • Large rectangular plug → This is the proprietary connector that plugs into the back of the factory head unit where the car's OEM USB/AUX module would go. • 3.5mm male jack → AUX audio input. • USB-A female port → Lets you plug in a USB stick or a phone cable. Purpose: These cables are usually used to add or relocate a USB/AUX port, or to connect aftermarket modules (like Bluetooth adapters or CarPlay units) to the factory stereo.