My old Rogers swivo/Holiday drum set had beavertail lugs. I used to think that the term "beavertail" described only the Rogers lug of that time period. Recently I've been reading about Slingerland beavertails and Anchor drums using beavertail-style lugs. So my question to y'all is, What makes a lug a beavertail? What are the features, style, or look that make a lug a beavertail?