For your consideration is ONE Genuine  NEW "SCUBAPRO" "S" poppet SPRING ONLY.... This SPRING fits many SCUBAPRO REGULATORS, to name a few  R-109 upgraded to S poppet, R-156 B&A, G-200 B&A, S-600 , A-700 and the world famous G-250.. Item Part number for this SPRING is # 01.020.216  This is the advanced "S" Poppet SPRING ONLY....If you need more photos or have questions just write me and I shall address your questions you asap.