White-Rodgers 37E73A-903 Gas Water Heater Thermostat Control Intelli-Vent Valve For Natural Gas Only

There are multiple versions of this thermostat. At some point they changed the ignitor connector from 3 pin to 4 on all 37e73a. So if you have an old model that has the 3 pin version, these newer thermostats will not work, unless you want to also replace the entire burner assembly. Also, there are different versions of the threaded thermocouple. The pictures on here are not enough to determine if this one will replace yours. The last 3 digits are critical I couldn't find any info here or elsewhere that gave the measurements of the threaded part of thermostat.