Lufkin® 636N Brick Masons Wood Rule Red End®, 6'Used by bricklayers. Graduated vertical inches to 1 16ths, both edges. Brick Mason scale on inside, red course counters numbered consecutively. Regular outside markings in black. Using the Lufkin "Red End" 636 Brick Mason's Rule is easy and fast. Used by bricklayers Graduated vertical inches to 1 16ths, both edges Brick Mason scale on inside, red course counters numbered consecutively Regular outside markings in black Using the Lufkin "Red End" 636