How does that work?

Well - actually yes I wanted to order only a better remote release with a slightly longer cable. 5 mtr. Kabelfernauslöser costs 15 euros and it is up to the nearly 20 euros this remote shutter release not more so far.
Well - the product has been delivered with the customary speed (amazon typical) in a usual rather large packaging. But the content was more surprising: the part looks quite wertig out for the price and thereby also a flash converter for Sony flashes on hot shoe flashes was packed with. But this thing (what really works with a real mid-contact flash - I've tried it) costs just 10 euros!

After first unpacked everything and assembled. OK - the battery of the siren is a 23A 12V - battery. They are quite expensive in the replacement, but for now all batteries are indeed doing. The batteries in the receiver are AAA - batteries that are commercially available batteries that I've replaced by batteries, which also worked perfectly.
The knurled screw for connection to the flash adapter is full plastic. Tighten Even without the receiver sits the recipient but pretty sure (well - somewhere you have to stop saving). The cable from the receiver to camera is about 20 cm long, which is enough perfectly.
The receiver can not be turned off, the transmitter. I will preemptively times the battery when not in use remove (reactive current?). The release button on the transmitter works very well - as usual from a camera, lightly press for focus, by pressing for cause, either directly or with about 2 seconds delay (via fairly stable slide switch selectable).. The antenna must be extended about 2 stages so that the transmitter sends. A wide measurement I have not done, but at 5 feet it works - probably even more (if necessary inquire times, then get I the time to). The frequency is by mice piano (4 dip switches) adjustable. While that is frumpy, but practical and straightforward.

Functionality:
I got on a Sony a55 and a Sony A350 attempts, both worked perfectly - you do not have the recipient of course put on the hot shoe - but it's just convenient that way.

Conclusion:
I am completely satisfied with the product, value is a mystery to me how you can sell this product for only 20 Euro. 5 of 5 stars (durability not taken into account - I have him only one day; o))