Monitor the temperature of your amps (or anything) and control fan speed vs a selectable temperature

Some might consider the TM-1 to be over-built; we think it is just right. Some features of the design are:

• Comes with both F and C temperature scales
• Mil spec FR4 circuit board
• Regulated power supply
• Constant LED current and brightness regardless of battery voltage (won’t dim with your beat)
• 20 bright surface mount LEDs
• Wide operating voltage range for vehicles with modified electrical systems
• fully variable fan speed drive system (PWM)
• Remote wired sensor with 18 feet of cable

Specifications

• Operating voltage range for power supply........8-22 VDC
• Display Range..................................................30-220 F or 0 - 100 C
• Fan Set-point....................................................40-200 F or 5 - 90 C
• Accuracy...........................................................+/- 5 F or 3 C
• Maximum Fan Load..........................................5 Amps DC
• Dimensions………………………....…....….......2.75 X 2.75 X 0.6 Inches

Owner's Manual (PDF)