Bore Tech’s Proof-Positive Nylon Chamber Brushes are 100% chamber safe and set the benchmark for all other nylon chamber brushes. This is due to the superior construction and engineered features that are incorporated into each and every brush.Unlike phosphor bronze bristled brushes, our premium Proof-Positive Nylon Chamber Brushes are strongly recommend when using fast acting copper removing cleaners such as our Eliminator Bore Cleaner or Cu+2 Copper Remover. These brushes are not affected by copper removing cleaners and will eliminate blue pat