MasterSeal Sonneborn NP1 121.2-oz Stone Paintable Polyurethane Window and Door Caulk

MasterSeal NP 1 (formerly known as Sonolastic NP 1) is a one-component, high-performance, non-priming, gun-grade, elastomeric polyurethane sealant. It requires no mixing and typically requires no priming to bond to many materials, including concrete and masonry. Used as an acoustic sealant, MasterSeal NP 1 reduces sound transmission in partition systems to support high STC values by sealing spaces around cut-outs and at perimeters of partitions.

One-component formula requires no mixing, helping to reduce labor costs
Joint movement capability ±35% provides excellent flexibility for keeping moving joints weathertight
Easy to gun and tool, speeding up application and making neater joints
No primer required for most construction materials lowering installation costs
Weather resistant for long-lasting weather tight seals
Compatible with non-rigid coatings and can be painted
Superior holding power for long-lasting roof tile installation