https://www.thefirearmblog.com/blog/2020/07/02/glock-gen4-guns/ "In an effort to intelligently preserve and grow the GLOCK brand and deliver uncompromised quality and maximum customer satisfaction, we are focused on our mission of future-oriented manufacturing technologies. This includes extending the latest Gen5 technology enhancements to the .40 caliber line of pistols. Availability will begin in October; however, the focus will be on supporting existing .40 caliber agencies on transitioning to the latest technologies within the law enforcement market. While we will continue to support fielded Gen4 pistols and agencies with Gen4 models, we have stopped 9×19 and .40 caliber Gen4 productions for the US commercial market. We look forward to bringing the performance improvements of the Gen5 technologies to other areas of product development." Curious if Gen 4 .40 have thicker slide like Brazil Police models.