From the T&C:
Cash-Back Rewards
19.
Flagship cardholders can redeem for $100 cash back at
13,245 points at the lowest level and can continue to redeem
in increments of $100 cash back and 13,245 points to a max
of $1,500 in cash back with 198,675 points.
No partial redemptions can be made. Cash redemptions may
be requested by logging on to Navy Federal Online Banking
and using the available link for redemptions. You
may also call 1-888-842-6328 and follow the automated
prompts to access your Visa Signature Flagship Rewards
account options. Your savings account will be credited for the
cash within 10 business days.