There's a few different ones you can use.

Red: 006-545-42-24 (100/110)
Green: 006-545-45-24 (105/115)
Grey: 006-545-61-24 (105/120)
Blue: 006-545-64-24 (105/128)

The first number in parenthesis is the temperature that the aux fan engages at high speed, and the second number is when the AC compresor will cut out.