POH KIT FOR CHECK VALVE AS PER RDSO DRG No. SKETCH- 98112 ALT. NIL, CONSISTING OF 04 ITEMS:-, 1 FILTER TO ITEM NO. 2, QTY = 1 NO., 2 VALVE SEALING RING TO ITEM NO. 4, 3 COMPRESSION SPRING TO ITEM NO. 6 QTY = 1 NO., 4 SEALING RING TO ITEM NO. 7, CONFORMING TO RDSO SPECN. NO. 02- ABR- 02 WITH AMENDMENT NO. 4 OF SEPT- 16 & APPENDIX- I.