American Express charge cards offer no pre-spending limit and you must pay your full balance on each statement.
American Express is now offering a pay over time option to allow you to pay these charges over time on eligible $100 or higher charges. They also want to incentivize you by offering you free Membership Rewards points just for enrolling. There is no fee to enroll.
There is the 5,000 Membership Reward option for non-Platinum cards
There is also the 10,000 Membership Reward option for Platinum cards
I would recommend taking screen shots of both the enrollment page and the registration complete page and as always, your mileage may vary. The credit should appear in 6-8 weeks.
I certainly would recommend paying your balance in full each month even if you enroll in this promotion.
Thanks to texasman for the tip