RM KL-243 43mhz linear amplifier

Anyone have any experience with them? Was told by the guy selling it at a hamfest its more wide band then what's advertised and that it can get on 6m though it may need some tuning of the internal trimmer capacitor. Don't know much about these and can't find much of anything online. There is a trimmer capacitor in there like he said, I just don't wanna go mucking with it blind unless I have to.

FYI, I only spent $35 on it so it wouldn't be a major loss if I couldn't use it.