Here is a hint, the Cyelee T10 on amazon, is currently going for $76.50 on amazon right now, and is just a rebranded Holosun. Its almost a direct copy of the Sig Romeo 5. For awhile they were even coming with the exact same SIG labeled torx key for install. Here's a link if your interested. https://www.amazon.com/dp/B076H2P916?ref=nb_sb_ss_w_as-ypp-rep_ypp_rep_k1_1_5&&crid=3EUPO600P953K&&sprefix=cylee