ZUOS A Pairs of Seamless Seam Setter with 6" Suction Cups for Seam Joining & Leveling​/​Professional Countertop, Granite， Stone, Marble Slab Installation. Two 6-inch hand pump vacuum suction cups for reliable hold Two fine-tuned adjustable knobs for precise leveling.A fine-tuned adjustable knob for seam joining or opening Achieve the finest seams for professional countertop installers Made with long-lasting stainless steel components and aluminum tightening handles for heavy-duty stone tops. Premium Quality with Excellent Customer Service: The glass lifter through the CE, SGS, RoHS, PAHS certification. Description How to use 6” Seam Setter 1: Place the fixed (left) suction cup on the left slab. Place the movable (right) suction cup on the right slab. 2: Pump the plunger until the suction cup attaches completely. 3: To join the seam, turn the side knob counter clockwise until you are satisfied with a seamless appearance. 4: To level the slabs, make sure one of the blue head under the top knob is on the higher side of the seam and turn the top knob clockwise until the slabs are leveled. Usually you only need to use one top knob to level. Use two when there are any expanding needs. 5: Lift the rubber tab on the edge of the suction cup to release the suction after seam has been completed. Specification： Size: 450*155*120mm Total length: 45cm Suction disc diameter: 15cm Package includes: 2* 6-inch seam setter for seam joining & leveling ​/​ professional countertop 1* Carry box