Jack.K, Refer to page 5 on Leshiy 2 Schematic Diagram on the EDgun West website under Resources: https://www.edgunwest.com/gun-schematics-r5m-lelya-leshiy/ .25 and .30 Cal. have only one jet (nozzle) and one screw; the .177, .20 & .22 Cal. have two jets (nozzles). The parts we need to have...