The perfect plexiglass jointer tool for white mortar to ensure a non-marred surface. Use this tool to make round, sunken, moisture-resistant rodded joints. This concave joint is the most popular masonry joint in the United States. Each end makes a 1/4" joint. Made from plexiglass and will not discolor or leave black marks on material. The shape of the tool provides knuckle clearance as you form joints. A popular tool used with glass blocks. The overall length of the tool is 11-1/4" long.
 
Creates a concave joint
Creates the most popular joint in the U.S.
Strong plexiglass construction
Will not discolor, mar, or burnish the surface
Forms 1/4 In. joint
Creates a moisture-resistant rodded
Designed for knuckle clearance
Popular with glass blocks and white mortar
Overall length 11-1/4 In.