Distribution block

"The rear half of the distribution block is totally separated from the front half." This statement is incorrect-my original distribution block from my"fruit jar" master cylinder is not separated .When I put air pressure to it air comes out of ALL the ports -there is no separation between front & rear with my original distribution block. It appears the rear port is of smaller diameter than the front but they are ALL connected.My original rear tee fitting also has smaller ports-but the one that I purchased to replace it has much larger diameter ports for whatever reason.