The Tourbillon Mechanical Watch compensates for the gravity - induced gain or loss with its mobile carriage . The Tourbillon Mechanical Watch , whose carriage is mounted on one side only , with no supporting bar , allows better visibility through the cutout window at 6 oclock . The watchs face ( and back ) is made of sapphire glass , making it scratch - resistant . The Tourbillon Mechanical Watch is a limited edition .

Question: What may be the reason consumers will buy the watch immediately ?
Answer: The number of these timepieces is restricted .The Toubillon is made of sapphire glass which is now limited .The Tourbillon Mechanical Watch will not be sold after 6 oclock .None of the above choices .