The NP3 was barely dry on the new Alpha, Bravo, and Charlie Glock slides from KE Arms before they rolled out a fourth model. The new Delta KE17 and KE19 Slides share the same feature set with the Charlie Slides including an integral RMR mount and plenty of serrations to improve manipulation. However, the Delta Slides go a step further by including lightening/cooling slot in the design of the forward serrations.
The Delta Slides are available for both Glock 17 and 19 compatible firearms and with three different finish options: NP3, Black Melonite, and Stainless Steel. Check out the Glock products page at KE Arms for details.