CT498 Igniter Erosion Gauge A special tool designed specifically to measure the firing end erosion wear of Champion CFM56 series igniters. Calibrated to determine the extent of erosion of the undercut area of the steel sheel not easily visible to the eye. The measuring tip is shaped to reach into the undercut, true-wear area. For use with Champion CH31806 and CH31900 igniters only. NOTE:The tool is not interchangeable with the CT492 which is similar. Size:61/4 in. x 41/4 in. x 11/2 in./15.8cm x 10.7cm x 3.8cm