Polished brass finish. Overall diameter is 6.5″. Made in the USA.
Back slot top: U shape 1-1/8″ x 1-1/16″ with tongue shape tab
Back slot bottom: upside down cross shape 1/2″ x 1/8″ (at skinniest) and 3/8″ (at widest)
Center hole is 3/16″ and has a 1/8″ hole 1-1/4″ below it
*See pictures for details*