Mechanical purge spray/pour guns are the best choice for concrete lifting and fan spray stud bay applications. The valving rod/mixing module design is better suited for these types of applications and Profoam offers training, service, and spare parts for all mechanical purge guns.
Air purge spray guns are the most popular choice for SPF contractors. They are referred to as “air purge” because a steady stream of air flows through the mixing chamber and spray tip once the trigger is released to purge any residual material from the inside passages in the gun. Both Graco and PMC make great air purge spray guns and Profoam offers training, service and spare parts to support both products.