Here is a wonderful Federal Glass milk glass coffee mug with reindeers, Santa and CHRISTMAS 1975 in red. The bottom has an embossed F in a shield with USA 40. The cup is just over 3-in Tall, and 3-in Wide not counting the handle.
The mug is in excellent condition except there is a tiny chip on the footed bottom. I tried to catch it in the last picture. What a great gift for someone with a wonderful memory of Christmas 1975!