No marking of brand but with Kirsch items in my workshop Pair in this lot Length is 3 inches with extension of 1.5 inches Check photos for quality
(1) Vintage Kirsch Heavy Duty 3/4″ Curtain Drapery Rod Center Support Brackets
These have a maximum projection of 4-1/4″. Brackets are in excellent condition with very few scratches. Mounting screws are included. Center Support #56.