Here’s what Felix Klein had in mind back in 1882, when he first dreamed of a closed, one-sided surface. It’s elegantly curved, with a side loop making a transverse puncture at the nexus. An Acme Classical Klein Bottle is big enough to show to a classroom, yet slides easily into your backpack for trips across the Yukon. With its center of gravity directly over its base, your Acme Classical Klein Bottle stands on its own — no need for extraneous stands, complex levitation apparatus, or unreliable anti-gravity fields. Indeed, in the absence of external forces, its polhode rolls without slipping on the herpolhode lying in the invariable plane.