The Marshall 1965B Lead 4x10 is a speaker cabinet for use with any guitar amplifier head. I've used it both with a Marshall lead and otherwise, as it's useful no matter what head you're thinking about using it with. Like the name suggests, it's got four 10" speakers inside of it, which is smaller than your average cabinet that will have 12" speakers. The cabinet only has a 1/4" speaker jack in the back of it for plugging in your head, but beyond that there isn't anything in the form of controls or connections. The studio I work at has one of these and it's really the only separate speaker cabinet that we have. We have it for use with our Marshall JCM800 head and it also will see occasional use with our Mesa Boogie Dual Rectifier head. Either way, the cabinet does it's job and it does it's job well. Any speaker cabinet will only sound as good as the head you're sending to it, but with this head you can definitely rest assured that what you're hearing is the amp and the amp alone. I don't really know what the availability of this cabinet is, as I don't believe it's being made any more and don't know how many used models are floating around out there. I like the 4 x 10 size, as I don't think 4 x 12 is really going to be necessary all the time, least of all in the studio where you're most likely only going to be mic'ing up a single speaker anyway. The bottom line with speaker cabinets is if it portrays the amplifier accurately, and I haven't found anything with this cabinet to suggest otherwise. I'd definitely recommend the Marshall 1965B Lead 4x10 as a smaller speaker cabinet option for use both in the studio and elsewhere.