Do not attempt to drill the rail without a suitable drill bit. A normal hit will destroy it. These chain bits melt through the chain, sealing the cut (and included reinforcing cord) in their path. What remains are clean cuts and many small souvenir rubber stoppers throughout the country! Important Tip: Use a bowl of soapy water to cool the bit between holes. This will help lubricate the cut and prevent the drill bit from overheating.