Wonder if it's from Amazon directly, or from a 3rd party seller?
Sometimes sellers do make mistakes. I've seen a watch suddenly had a seller selling for over $100 cheaper than lowest price offered by Amazon. I don't remember the model on top of my head, but it's something easily confuse with another model. Only a few hours later, the seller changed the price back to what normally would be. They were lucky that I had no interest of buying that watch, but not sure if anyone else got to it before they changed the price again.
In this case, may be someone confused between a Gulfman and a Gulfmaster! LOL ;-) Let's hope the OP actually getting an authentic watch. The Gulfmaster is MSRP at $500 USD, and the cheapest deal you can find out there is $300 USD. $99 is totally unbelievable!
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