A Nearly Universal Fan Clutch Wrench Set for Use on the Most Popular Applications. Unique hooked wrench design will hold bolted on water pump pulleys by applying pressure against another bolt. The double-sided spanner style holding wrench will hold pressed on pulleys on many GM, Jeep and Dodge vehicles. The double-ended turning wrench will work on 36mm and 47mm/1-7/8" sizes. 1/2" square drive holes in the tools are for use with a hand ratchet or breaker bar to create a handle and allow extra force to be applied. *Will not work on Dodge Hemis *Does not work on GM Duramax (Diesel)