Mapei Mapeflex MS Crystal Transparent Crystal-Clear Hybrid Elastic Sealant and Adhesive 300 ml

Mapeflex MS Crystal by Mapei is the benchmark hybrid elastic sealant and adhesive for those who do not want to compromise between visual appeal and technical performance. Its crystal-clear transparency — unlike the typical opacity of traditional silicones — makes it practically invisible after application, preserving the original look of any surface.

Formulated with silylated polymers, it is completely free of silicone and isocyanates, requires no safety labelling on the packaging, and is certified EMICODE EC1 R Plus for very low emissions of volatile organic compounds (VOC): a responsible choice for residential, healthcare, and work environments.

As a sealant, it elastically handles cracks, gaps, perimeter joints, and expansion joints subject to movement of up to 20%, both indoors and outdoors. Typical applications include facades, internal partitions, glass walls, windows and doors, shower enclosures, and the junction between skirting boards and flooring.

As an elastic adhesive, when applied in a thin layer it provides a permanent bond for the most common building materials. It is particularly suitable for shelves, ledges, and glass objects, as well as transparent plastic components. It adheres to glass, wood, metal, ceramic, stoneware, aluminium, and many plastics, even on damp substrates.

Main technical features:

• Movement capacity: 20%
• 100% elongation modulus: 0.6 N/mm²
• Shore A hardness: 35
• Working time: 20 minutes
• Coverage: approximately 3 linear metres per 300 ml cartridge (10x10 mm section)
• Emission certification: EMICODE EC1 R Plus
• Complies with EN 15651-1 (F-EXT-INT), EN 15651-3 (XS1), ISO 11600 F20 HM

Make sure the substrate is solid, clean, dry or at most damp, and free of dust, friable parts, oils, grease, or release agents. For unstable surfaces or joints subject to high mechanical stress or frequent immersion in water, the use of Primer FD is recommended. For applications on plastic materials, it is preferable to use Primer P combined with light surface sanding; a preliminary test is recommended in any case.
Apply the product directly from the cartridge using an extrusion gun. To avoid soiling the edges of the joint during application and finishing, apply adhesive masking tape along the edges and remove it immediately after smoothing the sealant.
If painting, wait until the product has fully cured and use elastomeric paints.
Do not apply at temperatures below +5°C. Do not use on bituminous surfaces with possible oil exudation. In case of prolonged exposure to UV rays, surface yellowing may occur.

The product is contained in a plastic cartridge (polypropylene). Once empty and free of product residue, the cartridge should be disposed of in the plastic recycling collection, according to the procedures established by your municipality of residence. Always check local guidelines for proper disposal. Do not release into the environment.

To safety data sheet