The 4″ Log Cabin Trim Tool Template features exclusive markings to create perfect Log Cabin, Half-Log Cabin & Courthouse Steps blocks by squaring up each round of logs as you go. After adding each round of logs, place the appropriate centering square on the ruler over the 1 1/2″ finished center square and trim. Since each round is squared up before the next set of logs are added, the results are spectacular. The suggested strip widths are printed right on the template!. Tool features exclusive gripper dots to prevent slipping.