Aluminium seal relic

[Danmark]

Hi all,
Sometimes the smallest things are the most intriguing. Such is the seal that turned up in a group of dug relics I recently bought from a seller in Latvia.

It is stamped H. & V.K. 1938 but the neat thing is the waffenamt stamp of WaA186 that emerged after cleaning ...BUT, here's the problem, from what I can see WaA186 was assigned to R. Ehrhardt Pössneck, Thüringen in 1937 or Karl Böcker Waldbröhl, Rhld. in 1940

So, any idea a) what it was sealing? and b) who was H V & K?

Thanks as always ..... Dan