This base was custom built for the marlin 39a and is blued steel.It is one of a kind . It has a channel cut so with the scope removed you can use the factory iron sights . It also has a groove cut underneath so the sight ramp can function. It is about as clean of look as you could get on a 39a for weaver style rings. Very good craftsmanship. It cost me a lot to have made so it’s expensive, but if your looking for something that is high quality and custom for a nice gun this would work well or if you just want rugged and reliable this will do that too.