I ordered the screws that have been missing since the appropriate screws for the wall brackets for my Logitech Z906. The wall mounts were suggested to me by Amazon to the plant. The screws that came, but unfortunately have not fit because the satellite speakers have a UMC 1/4 "thread. Thus, I have ordered these screws. The screws were within 1 day (without Amazon Prime) with me. The screws fit perfectly for the Logitech Z906 and I can recommend to anyone who also has the same problem as I only!
Conclusion: 5/5 stars: Price / Quality Top, super fast delivery - what more could you want?!