Use the Lisle Universal Fan Clutch Wrench Set, No. 43600, for use on the most popular applications. The unique hooked wrench design will hold the bolted-on water pump pulleys by applying pressure against another bolt. The double-sided spanner style holding the 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. The 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.