P365 micro-compact 9mm pistols, which come with an included red dot. The new P365X ROMEOZero gets its designation from the fact that it combines the 3.1-inch barrel of the original P365 with the P365XL XSERIES grip module, giving it a 12-round flush-fit magazine, and comes with a factory-installed ROMEOZero red dot. The latest P365 is the P365X ROMEOZero which, as its name suggests, includes a Sig Optics ROMEZero micro-open reflex sight. (Photo: Sig Sauer) The Sig Sauer P365 series of pistols is the leader in the industry for everyday carry and continues to set the standard for delivering unprecedented capacity in a micro-compact size,” said Tom Taylor, Sig s CMO and executive VP for Commercial Sales. The introduction of the P365X ROMEOZero further redefines everyday carry by combining the XSERIES features first introduced with the popular P365XL – including the larger grip module and XSERIES trigger – with the shorter 3.1-inch barrel of the original P365