Johnny Rockets – Original Milkshake for $2 (reg $4+) through May 10, 2018

Johnny Rockets restaurants offer the following coupon.
Original Milkshake for $2.00
Chocolate, Strawberry, or Vanilla
Price is regularly around $4.29.
Valid through May 10, 2018
Not sure if you need to print out the coupon or if you can show on your phone. It says, "must surrender to redeem." That implies printing it out & giving it to them. Or maybe it means surrender yourself and you will be redeemed.
One per table. Not sure if you can order to go. Valid at participating locations.
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