The one on the left is a recently acquired MIVA BT1. It's a whopping 6-1/4" across the bar and is 4-5/8" tall, and is one heck of a paperweight.

Pictured with it for scale are a BT2 (CD 678), BT2M (CD 677.7), and BT4 (CD 677.3B). I'm still searching for the BT3 and BT3M.