On August 5, 1958, Edward Hack received U.S. Patent Nos. D183309 on his whirl bottle, and D183310 on his pineapple bottle:
These bottles were briefly used to sell flavoring for milk, chocolate in the whirl bottle, pineapple in the pineapple, and strawberry in a third, strawberry shaped bottle
An article in the 1957 issue of The Chemist and Druggist magazine explained:
Milk Made Irresistible. — A new series of flavours for milk, cereals, sandwiches, cakes, pancakes, spreads, jellies, blanc manges, custards and ice cream is being marketed in hygienic polythene easy-squeeze shapes, by Flip, Ltd., Lion House, Red Lion Street, London, W.C.I. Issued in three varieties (strawberry, pineapple and chocolate), the Flip flavours are sent out 1 doz. of each flavour in polythene bag. Three bags are the complement of each ‘outer.’