Based on colorFabb_XT, XT-CF20 is a carbon fiber composite material. Loaded with no less than 20% specially sourced carbon fibers we have developed a very stiff and tough 3D printing filament made for functional parts. It is truly a professional printers go-to material, especially for users looking for high melt strength, high melt viscosity and good dimensional accuracy and stability. Please note: A special point of attention is the abrasive nature of the carbon fibers. In general these fibers will accelerate the nozzle-wear of brass nozzles, much faster than unfilled filaments. We recommend to use from stainless steel nozzles or nozzles made with hardened copper alloys.