Mix crushed pretzels, sugar and butter. Press firmly onto bottom and up side of
9-inch pie plate. Refrigerate until ready to fill.
Combine condensed milk, lime juice and drink mix in large bowl until well blended. Remove 1/2 cup whipped topping and store in refrigerator until ready to serve. Gently stir in remaining 2 1/2 cups whipped topping. Pour into crust.
Freeze 6 hours or overnight. Let stand at room temperature 15 minutes, or until pie can be easily cut. Garnish with reserved whipped topping. Store leftover pie in freezer.
