Seal-it® 478 PU-STONEFIX

Seal-it® 478 PU-STONEFIX is a high-quality, durable, waterproof and ready-mixed polyurethane adhesive that is particularly suitable for adhesion of various stone types, including gypsum, concrete, cellular concrete and sand-lime bricks, for non-load-bearing walls, that moisture-cures into a strong adhesive bond.



  • Particularly suited for adhesion and installation of non-load-bearing floor, façade and interior and exterior wall structures.
  • As a mortar substitute for adhesion and installation of stony building components/materials, such as plant and flower boxes, blocks, stones, stone strips, tiles, edges, decorations, mouldings, seating blocks, thresholds, window sills, window banks, sections and roof tiles.
  • As stone adhesive for adhesion and installation of numerous stone types, such as natural stone, masonry, cobblestones, sand-lime bricks, cellular or non-cellular concrete parts and ceramics.


  • Ready-to-use, fast-curing PU adhesive.
  • High tensile, shear and ultimate strength, fast-strengthening.
  • Versatile, both indoors and out: adheres, installs, fills and seals.
  • Strong adhesion on many surfaces, even moist ones.
  • Very low emission: certified VOC emission class A+.
  • User-friendly, fast, dust-free, zero-energy application that requires no cleaning, with the Seal-it® PU gun.
  • No mortar, cement, nails or screws needed.
  • Lightly filling/foaming adhesive and mounting system.
  • Efficient, very low/economic adhesive use.
  • Excellent resistance to hot and cold conditions, water and many chemicals.
  • Lasting resistance to weather, moisture, water and ageing; does not rot.

Application conditions

  • Application temperature (ambient and surface) between +5°C and +40°C.
  • On compatible, stable, clean, uncontaminated and grease-free surfaces.
  • Use a suitable brush to remove any loose particles from the surface.
  • Degrease the surface properly using Seal-it® 510 CLEANER.
  • Give the canister approx. 20 good shakes before use.
  • If necessary, use a plant sprayer to lightly moisten the surface in advance.
  • Cut off fully cured excess Seal-it® 478 PU-STONEFIX with a knife and/or trowel.
  • Before use, grease the threading of the gun adapter with Vaseline, PTFE and/or silicone spray, to prevent the canister sticking to the PU gun.
  • After securing the canister on the gun, the spray speed and output volume are adjustable using the setscrew on the back of the gun for efficient/economic use.
  • When not in use, tighten the setscrew on the back of the PU gun until it is closed so the PU gun can no longer be activated.
  • Always leave the canister in the PU gun until it is completely empty.
  • Remove the empty canister by holding in the trigger while unscrewing it in order to expel any remaining propellent gas.
  • Next, reload the PU gun with a full canister and/or clean the PU gun thoroughly using Seal-it® 450 PUR CLEANER.
  • If the PU gun is not working properly, put Seal-it® 450 PUR CLEANER on the PU gun. Spray through several times and let set well for approx. 15 min. Spray through again and then remove the Seal-it® 450 PUR CLEANER canister.

Standard product line


12 x 750ml canister



SI-XXX-XXXX-XXX = Article number.
Other colours and/or packaging on request.


  • VOC emission class A+

Technical support department

Connect Products has a state-of-the-art R&D laboratory, where experienced specialists continuously research and develop sealants, adhesives and PU foams. Customers and clients can have products researched, tested and developed by this department. You can also contact us for technical advice, tips, project support, warranty certificates, requests and other technical questions. We will be happy to assist you with high-quality technology.

Call us on +31 (0)183 731 400 or send us an e-mail.

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