Nice box :D
The box is very utilitarian - I like it! A simple instruction manual, the mic and its clamp. The instruction manual indicates that this mic has a Super Cardioid polar pattern. Not sure what's with the massive side grills, but the mic's an end fire mic, and it comes with instructions as well as text printed on the mic casing to indicate where it picks up sound from.
The clamp does not come with an adaptor for the smaller threadsize used in the UK, but the PR31 does fit into the SM57's mic mount. Barely.
It is ridiculously small. The Heil PR 31 BW uses a similar element to the PR 30 (that I really would prefer - just for the fact it has a RED grill :D). However, the PR30 is somewhat larger and would not fit properly in the Studio Projects Reflexion Filter. This will... but would there be a point to using the reflexion filter with a dynamic, I wonder.
Since this is a super cardioid - it does pick up an attenuated amount of sound from behind the mic. The reflexion filter _may_ help in this case.