The lonsdale is the elegant middle: longer than a corona, thinner than a Churchill or toro. Classic tables put it near 6½ × 42. As always, factories wander.
The thin ring keeps the wrapper in the conversation. The extra length gives the blend time to change as heat moves up the cigar. It is a size for people who like a parejo that does not sit like a log.
Named, in the older trade stories, after the Earl of Lonsdale. The association is traditional. This page does not treat the peerage as a blending note.