This is a Peerless dwell tachometer Model 425. it is used with the instructions.
Vintage Sun Dwell Tachometer Engine RPM Dwell Tester
Vintage Peerless Dwell Tach Primary Analyzer Model 455
Vintage Penske Dwell Tachometer Sears Roebuck and Co 244.21013 Made In USA
Vintage Sears Dwell Tachometer 161-2177 Diagostic Tool With Manual In Box
