Used by bricklayers for spacing brick courses Spacing range 2-7/8 to 3-1/2 in 1/16ths increments Brick spacings identified by black letters A-K Rule is printed in yellow Regular outside markings in black Brick Masons scale on inside, red course counter numbered consecutively Carded - For Over Sized Brick Wdth In x Lgth Ft=5/8 x 6