3m Ac 251

3M™ Aerospace Sealant AC-251 Gray Class B are two-part, quick curing, polysulfide based canopy and windshield sealants. These products are formulated for sealing acrylic, glass, and polycarbonate aircraft canopies and windshields. 3M AC-251 Gray Class B Sealants contain no solvent and do not craze. The sealants quickly cure and exhibit excellent adhesion and resistance to UV and weather exposure. 3M AC-251 Gray Class B Sealants have a thixotropic, non-sag consistency. They can be readily applied with a spatula or extrusion gun on vertical surfaces.