The SIG P250 has been discontinued. Mine came with regular sights. The rear sight is a weird proprietary thing no one will ever reproduce. CDNN has the rear night sight for sale for $10, with $10 shipping. (ouch). So if there are any SIG P250 owners wanting rear night sights, here's your chance:
https://www.cdnnsports.com/sig-sauer-p250-rear-night-sight.html#.WfKVUWeWw5s. I've heard the front sights are regular SIG, but haven't checked yet. I didn't know if I wanted night sights at all, but that price was just too good.
