If back lit, light will shine through. The amount of brightness is dependent on the strength of the light.
NOS vintage Simpson Large volt/panel meter Sun? engine analyzer 1950s 1960s
1948 Sun Motor Tester Master Model Parts #50 Combustion Booster Engine Analyzer
Vintage Sears Engine Analyzer 12 V Model 28-2161 Engine Analyzer w/Box- TESTED
VTG Tester Gauges For Combustion Compression & Sun Engine Vacuum Model CP-7801
Vintage SUN Engine Compression Tester Gauge CP7824 300 PSI
Vintage Sun Engine Vacuum Tester Gauge With Hose
