Picked this one up lately just for the swirly folds in the glass. I had avoided collecting glass power insulators for like 35 years, but a few years back I started to dabble in those. Now I am picking up glass power pieces at an alarmingly regular rate! This one is a CD 296 EIN [020] thus marked: Front: F.M. LOCKE VICTOR, N.Y. Back: No 20. Generally weak marking, but no blot outs.