The TRACER Clog Free Marker Twin Pack Black includes 2 x 2–4mm bullet point clog-free permanent construction markers designed for the toughest, real-world job site conditions. Engineered with an advanced clog-free ink formula, these construction markers are built to perform where others fail—marking reliably on dusty, oily, wet, shiny, and even rough surfaces without drying up or becoming blocked. Whether you're working with timber, metal, concrete, brick, tile, plastic, or glass, these markers ensure bold, highly visible black lines every time. The durable 2–4mm bullet tip produces thick, consistent lines ideal for marking, layout, cutting, and measuring tasks. Unlike standard permanent markers, TRACER's clog-free technology delivers long-lasting, fade-resistant performance with every use. Plus, they are xylene- and toluene-free, making them a safer choice for workers and job site environments. A reliable brand trusted by professionals globally, the TRACER clog-free marker is built for precision, durability, and clarity on every surface.