Simple switch between tach and dwell modes. Works with 4, 6, and 8 cylinder engines.
Vintage The All American Dwell Tachometer Model 549 Rite Autotronics Pre Owned
Vintage RAC The "All American" Dwell Tach Tachometer #549 Untested
Vintage Sun Dwell Tachometer Engine RPM Dwell Tester
Vintage SEARS PENSKE Dwell Tachometer 21013 In Box UNTESTED
Vintage SEARS PENSKE Dwell Tachometer 21013 In Box & Owner’s Manual
