Beware of imitations! This tool was originally designed by Motion Pro over 30 years ago. Since then, many of Motion Pro's competitors have tried to copy this tool, but none of them have got it quite right. Over the years they have added several new, not so obvious features that enhance the function and durability of this tool. You won't find those features on the copycat versions. You can only get the original and best folding chain tool from Motion Pro. Original Motion Pro design. Fits 420 to 530 pitch chains. Will push link pin completely through link / side plate. Handle folds away for easy storage. Durable drive pin is heat treated for strength and wear resistance. Max pin extension to drive out chain links is 18 mm (the maximum pin extension required to drive out the chain link is determined by measuring your chain's width from outside face plate to outside face plate).