Question about Kingston ValueRAM

Yes.

Short answer: Better buy RAM with the required speed (1066Mhz / PC3-8500); digitec item number 228615

Corsair ValueSelect (1x, 4GB, DDR3-1066, SODIMM 204)

Long answer:
Mechanically it would "fit" but unfortunately the MacBooks are a bit picky about exact speeds. Although theoretically the DDR3-1600 module would allow slower speeds, it is very likely not recognised at startup. Sometimes it works if at least one module is "only" 1066Mhz/PC3-8500 fast. Another possibility would be to manipulate the JEDEC configuration (with a special programme on a special mainboard) so that the "too fast" module is only recognised as 1066Mhz/PC3-8500. Conclusion: buy the right module (see short answer)...

Thank you for the answer.
It is clear to me that the speed should fit.
However, when I check with Apple, I am given the following specifications for the RAM for my specific MacBookPro model (15", mid 2009):

Memory card specifications
- Double Data Rate Small Outline Dual Inline Memory Module (DDR3) format
- 30mm (1.18 inch)
- 2 GB or 4 GB
- 204-pin
- PC3-12800 DDR3 1600 MHz type RAM

This does not match your specification of 1066 MHz.
What is valid now?
Thanks in advance...