Snip- I examine the bottle carefully, using such clues as cap placement, orientation of any printing or labels,... Snip You must also check the heat shrink seal. There are 2 mil seals and 3 mil seals as well as others out there. 2 mil is much more prone to distortion in the shrinking process. It can crinkle and bunch to one side. This displacement of 2 mm square of plastic could be the cause of much imbalance. -Jim C still trying to get planted. MWPH