Originally Westinghouse the Cutler hammer/Bryant type BRD model BD-20 15 with 2 single pole breakers in a 1 inch case.
One breaker is 20 amp and the other is 15 amp.
Price for used is $10 each, price for new is $20 each.
Bryant 2X single pole circuit Breaker Block
C$10.00Price
905 981 7393