I've got both the 870 (several actually) and the Ithaca 37. My Ithaca is a 20" barrel model with the extended magazine.
For pleasure shooting, blasting, FUN, you did well in choosing a used police Ithaca. It doesn't have a disconnect and you can hold the trigger down and fan fire it (that is, every time the action is pumped closed, the gun will fire - just keep your finger on the trigger). It empties as fast as you can pump it. Keep the muzzle in a safe direction if you're going to go wild like I did.
We have an old thread here which discusses some of the other guns (Win 97 and Win 12 as well as a few others) which also had this wonderful feature.
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