Not enough grip to do anything. A complete waste of money unless you fit a clean caliper/piston. Still, the best it can do is rotate the piston to align it (depending on your calipers if you need to align them by pad/angle - my Porsche 911 needs them in sync). Think of it like an inverted vise tool. But on the inner piston, it is simply impossible to remove a dirty piston with friction from age and dirt. save your money And of course it's a cheap product from China. If Vise-Grip releases a version I might give it another try, but it's a gimmick in my opinion. Even though it's too expensive for what it is. It "feels" like a $9.99 tool from Harbor Freight (you know the guy - use twice and it breaks - disposable tools). water compression (if you have the tools) or my favorite grease gun compression (works great but you have to deep clean the caliper to remove the grease afterwards - look it up, it'll change your life).
JQuad Safety Orange Powder Caliper
9 Review
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Universal Car Ratcheting Caliper Piston Tool with 2 Steel Plates - Brake Caliper Press (Red, Two Size)
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ABN Brake Drum Tool Kit - 15-Piece Service Brake Kit with Spring Pliers, Brake Spoons, Pad Gauge, Brake Spring Tool
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