Is the Invicta Pro Diver 8927OB a real automatic watch?

Yes. It uses a Japanese automatic movement, so it winds from wrist motion and has no battery. You can also hand-wind it and set the time through the crown.

How does the 40 mm 8927OB compare with the 43 mm Pro Diver?

It is the same dive-watch formula in a smaller case. The 40 mm version suits wrists that find the 43 mm models too large, and it keeps the rotating bezel and automatic movement.

It is rated for water resistance, but the crown is push-pull rather than screw-down. Many owners keep it out of serious water use and treat it as a desk diver.

Does it have a sapphire crystal?

No. It uses a mineral crystal, which is more prone to scratches than sapphire. Replacement crystals are available if yours gets scuffed.

The watch on its gold-tone bracelet, a manual and Invicta's yellow presentation box. No extra strap or tools are included.

Is the gold-tone finish durable?

It is a plating over steel, so it can wear or fade at high-contact points over years of daily wear. Treating it gently and wiping it after use helps it last.