Professional Countertop Tools: The durable stainless steel beams and quality machined aluminum tightening handles make it long-lasting and ideal for heavy-duty coutertops. Strong Suction Power: The 6" vacuum cups are made from natural rubber and are airtight for reliable, long-lasting attachment to the slab. Easy to Use: 2 pack seamless seam setter with 2 adjustable knobs, one for precise leveling, another for seam joining or opening. 2 small hexagonal spanners for adjusting the buttons on the device. Perfect Joining & Leveling: Seamless seam setter is designed to pull two flat non-porous surfaces or seams together. Idea for marble, granite, flooring mirrors, glass, quartz, etc.