For your consideration, Garrett Park Guitars presents this Boss AC Power Adaptor.
From the Boss website:
The PSA series is the recommended power supply for products including all new BOSS compact and Twin pedals, multi-effects and more.
- 500 mA of current to easily power multiple pedals, even digital ones
- LED indicator for quick visual verification of on/off status
- New design which does not cover adjacent power outlets
- Sold as PSA-120S in the United States
