Our 3/4″ split rivets are brass plated steel; shiny gold in color.  The head is slightly domed and is 7/32″ in diameter; just under a quarter of an inch. Shank is 3/32″ in diameter and 3/4″ long.  The legs make up part of that; they’re 1/4″ long.  This is RVT-134, sold in packs of 50 for $8.00, USA shipping included.