Surly Surly Big Dummy Frame Protective Plug Insert.
– Notice the tapered end of each plug, if the end of a tube is dented, tap the protective plug into the tube with a soft hammer to round the tube out – Designed to prevent damage to the front bridge tube while frame is being shipped – Doubles as a tool to help round out any damaged bridge tubes or upright tubes during use of the bike – The diameter of the plug is designed to round it out to the correct diameter so that it receives accessories properly
