Horizontal Colorseal Watertight, HorizontalPlane Expansion Joint Sealant for NonTrafficked Applications. Horizontal Colorseal is ideally suited for ensuring watertightness in horizontalplane structural, seismic, and abutment joints in nontrafficked decks of castinplace, precast or posttensioned combines a factoryapplied and cured silicone bellows with a hydrophobicacrylic ...