BOSS Bass Limiter LM-2B. Operation has been confirmed with both AC adapter and battery. I believe there are no issues with scratchiness. The model name display is faint and difficult to see, but there are no problems with use. The BOSS Bass Limiter LM-2B is BOSS's first bass limiter, featuring LEVEL, ENHANCE, and THRESHOLD controls. It's a bass-specific limiter & enhancer that also includes an enhancer function to bring out the presence that can be lost when using a limiter. Please refrain from purchasing if you are looking for perfection. We are looking forward to your purchase if you understand that this is a used item.