This is a genuine BMW solenoid valve (SOLV), part number 24 34 1 423 368. The number stamped on the part is 24341423368; BMW's catalog files it under the short number 1423368. You will find it on our Transmission shelf, under Other Automatic transmission parts.
It fits every E46 body style (320i, 323i, 325i, 328i and 330i, 1999–2006), with the M52, M54 or M56 engines — and the European-market versions.
BMW draws it on the A5S325Z pressure regulat./solenoid valve (24_0894) diagram. BMW's catalog calls for three of these at each place it is fitted. It weighs about 90 g (0.2 lb).
We have not had one on the shelf yet. Request it and we will tell you when one comes off a car.