This is a new OEM Sig Sauer P229 RX Slide Assembly with Romeo1PRO optic preinstalled. It included suppressor height contrast sights. This will work on US-made P229-1 9mm pistols that came with 15-round magazines. This will not work on original P229s or P229 Legacy models that shipped with 13rd magazines. Also compatible with US made P229's chambered in .40 S&W or .357 SIG.