I have a newer one and an older version. My newer one (metal spring) is higher pitched than the older (rubber band) version.
I have tried a few different push pins over the years, and these Quaker Boys are pretty decent calls given their mass production and price tag ~$20.
I love push pins, they are my primary call. You should try to find one of Shannon Kelly’s push pins. He is “Old Gobbler” on this forum. Like I said, I collect push pins and nothing sounds like Shannon’s. The clucks, purrs, and yelps on his calls are the most realistic I’ve heard yet. They are very tough to get, but if you search hard, you may luck out. Good luck, be safe...