A small 50ml pill container.
This cache is part of the Blockbuster A to Z series.
An old 80's gameshow in which contestants had to pick letters and answer questions relating to that letter to get across the board and win.
If we were doing a modern day geocache version of this I would imagine it would go:
U.N.C.L.E: "I'll have a Y please Natalie247."
Natalie247: "This is a puzzling one indeed: At S46 12.YYY E169 38.XZX,
where YYY = (247 x 3) + 64
and X = Lowest common multiple of 2 and 3
and Z = half of X. ?"
U.N.C.L.E : "So Y must be at....."
Natalie247: "Correct - you won't need to store that away for later to see where i go with it."