CAUTION! Acme Klein Bottles are crafted from glass, an inorganic solid in an amorphous non-crystalline state. If dropped, an Acme Klein Bottle may shatter, possibly into paired single-sided Möbius loops. But then again, it may not. Other shocks -- including fast decelerations and Republican landslides -- may lead to similar fragmentation. Hand wash only, do not tumble dry.

During earthquakes, your Acme Klein Bottle may jump off the table, in a mistaken attempt to reconnect with the 4th dimension. So just before major tremors, apply a dab of quake-putty to hold down your manifold during the Big One.

IMPORTANT INFORMATION FOR IDIOTS: Non-metric topological manifolds may be considered ideal elastic objects, able to be bent, stretched, twisted, or deformed as long as nearby points in one space correspond to nearby points in the transformed version. However, Acme Klein Bottles are physical instantiations of such mathematical concepts. As such, they should not be subject to transformations which substantially increase the material's internal stress tensors. Specifically, please recognize that dihydrogen monoxide has a coefficent of expansion which is negatively correlated with temperature near its freezing point, and thus expands when changing from liquid to solid. This increase in volume can cause stresses within a containing vessel. Borosilicate glass -- such as that which Acme uses to manufacture its fine Klein Bottles -- has a finite capacity to absorb these stresses and retain a linear stress-strain relationship. When a certain stress is exceeded, the intermolecular silicate bonds will delaminate, resulting in stress-induced fractures. In other words, FREEZING WATER EXPANDS AND WILL SHATTER YOUR KLEIN BOTTLE. If you fill your Klein Bottle with water and then put it in your freezer, tomorrow morning your housemate will discover shards of glass in her raspberry popsicle. If still in doubt, please read the suggestion "For best results", mentioned 3 paragraphs below.