LM-HH4AS-H21 - 

Honeywell LM Series LCD Hour Meters
The LM series has been designed as a sealed, digital hour meter suitable for monitoring and recording elapsed running time. This is displayed on a digital LCD and normally shows hours and tenths of hours. They are ideally suited for applications where maintenance needs to be carried out on expensive manufacturing or transportation equipment after a desired time frame of operation. For added protection these devices feature a 40-year memory data retention without power. They also have a long reset time to offer customers the protection against malfunction of reset.