Whatever you get, get one you can use with an impact gun.
Not the same style, but I have this one:
http://buy1.snapon.com/catalog/item...&group_ID=1634&store=snapon-store&dir=catalog
It's meant to be used with an impact gun. If you can't use it with an impact, look elsewhere. Not sure how you can tell though. I can do a set of springs in no time using the impact.
BTW, the Snap On spring compressors are imports...they still work well.
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Anyone know what the deal is with this one?
http://buy1.snapon.com/catalog/item...&group_ID=1634&store=snapon-store&dir=catalog
Seems like the other piece is missing or it's supposed to screw into something. It's genuine SO, though, with the genuine SO price.