Cross Speccing these cylinders. Cross Speccing these cylinders. lenthezhongwen (Industrial) (OP) 2 Jun 16 06:09 If I wanted to crossover a parker model to another manufacturers model. How would I go about that? What basic information would I give the supplier? RE: Cross Speccing these cylinders. 2 HPost (Automotive) 2 Jun 16 13:40 Just give them the Parker part number. Let them do the work... I say that because that is what people did do me when I worked for Parker distributor. We also had no end of trouble with cheap knock off copies of the Parker seal kits. If they don't know the equivalent to offer you based on the Parker part number you give them, they are not worth your business.