Klein Bottle in 4D

During our discussion today about the standard model and alternative theories. We talked about Dark Matter, Dark Energy, and eventually string theory and multiple dimensions. I had only heard of a teserac and had never hearrd of Klein Bottles. I'm still trying to wrap my head around how  to visualize the Klein bottle as being contained in four dimensions. But that is what makes this phun! I'll just shake my head yes and smile.