Lefton brick (ten-hole brick, perforated brick) is made of clay or shale and has holes on it, that's why its other name is perforated brick. This brick is produced in large and small formats and in practical colors such as red, yellow and pink.

Ten-hole bricks can be found in the market in two sizes, large and small. In the production of small types, a small mold is used and these types of bricks have a yellow color. Lefton bricks of small format usually have yellow color and they are used in arching, sewer manhole and back work.

5 cm small leftons usually weigh 750 grams and are sold in packs of 14 to 16 pieces. Also, the weight of each of the other types of small molds, which are 5.5 cm, is between 800 and 820 grams.

When the brick is pressed on the soft mortar, some mortar penetrates into the brick through the holes, and as a result, the mortar takes the shape of the brick. In this case, the adhesion of mortar and brick increases. In addition, as a result of lateral forces, the resistance of bricks against displacement increases.