I own two Beyerdynamic headphones (DT 770 PRO and DT 990 PRO). The miniplug for both headphones is male-threaded (as the bigger jack adaptor enclosed on both is female-threaded) to ensure proper break-free connection.
Well, the problem with this extension cable is that neither male or female connectors has any thread at all, allowing for pops and breaks on the signal. I wonder how come such a brand as Beyerdynamic allows such a stupid design in a product bearing their name.
The connectors are so thick that male connector doesn't fit receased inputs nor the Beyerdynamic plug-adaptors either!
The thread problem is easily resolved with electrician's tape and in my case this is enough to keep it working. You may still have to get a non-threaded plug adaptor if you need to connect to a 1/4' input (as with most hi-fi application inputs).
I find almost 20 USD for a hi-fi audio product that complements the Brand's products so poorly is a very very dissapointing performance.
Maybe it is aimed for other Beyerdynamic products. I hope. For their own sake.