My wrist is also 6" and I removed several links on each side leaving three links on each side od the watch and it fits perfect. The watch is comfortable to wear since it is much lighter then it looks and also has a guard (moldng) where the link attaches to the watch giving it more comfort on you wrist.
I checked my watch and I also see screw heads in the sensor button. The watchband is stamped on the inside saying the band is made from "base titanium". The back of the watch shows that the back is made of stainless steel.