The Stanley Tools Chalk Refill in Red is a 225g professional-grade chalk specifically formulated for external masonry work where permanent marking is required. This red chalk variant is indelible, making it the ideal choice for long-lasting reference lines on brickwork, blockwork, and other masonry surfaces where marks need to withstand weather exposure and site conditions. Designed for use with chalk line reels, this high-grade chalk delivers bold, highly visible red lines that won't fade quickly on outdoor projects. The innovative square bottle design ensures it stays put on uneven surfaces and won't roll away, whilst the twist-to-open spout provides controlled, mess-free pouring when refilling your chalk line tool. Features and Benefits:Red indelible chalk ideal for external masonry work225g capacity for extensive project coveragePermanent marking withstands weather and site conditionsHigh-grade formulation for bold, visible linesSquare bottle design prevents rolling