The most common solid aluminum breadboard sold by Base Lab Tools is the 1/2" thick, black anodized optical breadboard with 1/4-20 tapped holes on 1" centers. Sometimes more flexibility is required in mounting patterns, so Base Lab Tools offers Double Density Hole spacing, offering the user twice the number of mounting holes.  It is two,  1" grid hole patterns offset by 1/2" in both the vertical & horizontal direction.  Additionally we offer custom standard aluminum breadboards up to 96" long.