This works perfectly with the standard business head unit, and is plug and play for the BMW Z4 (mine anyway, please check yours before buying.) No wiring necessary, unless you want to keep your bluetooth connection (if you have it.) Complete with loom, iPod cable (old type, not lightning) and AUX cable. It fits nicely in the cubby hole under the stereo and cannot be seen.
Looking for £75 including postage. Here's a photo:

Looking for £75 including postage. Here's a photo:
