The Fender LINK I/O is a USB audio interface for guitar practice. I am selling it because I no longer use it after buying a different amplifier. The product contents are as follows: ＜Product Contents＞ ・Main unit ・USB cable (Type-C to Type-C) ×1 ・USB cable (Type-C to Type-A) ×1 ・Box ＜How to Use＞ I used it connected as follows. I confirmed that it works not only on Android but also on Windows. Although I haven't tried it, Fender Studio seems to support iOS, macOS, and Linux as well. Guitar │ (Shielded cable) ▼ Fender Link I/O │ ├── Headphones │ ▼ Android smartphone (Fender Studio app) │ └── Simulate effects in the app (e.g., distortion, reverb, chorus, etc.) Mechanism: Guitar sound → Digitized by Fender Link I/O → Effect processing on smartphone (Fender Studio) → Processed sound played through headphones Result: Even without an amplifier, you can practice while listening to realistic effect sounds through headphones!