First Alert Z-Wave Combo Alarm - 2nd Generation?

Hi, I want to get one of the Ring compatible Z-Wave Smoke/CO Combo alarms and am a bit confused if there is a 2nd Generation version that is about to be released. **Amazon** shows two versions: Z-Wave Combo Alarm, Model Number: ZCOMBO. (in stock) Z-Wave Combo - 2nd Generation, Model Number: 1044807 (currently out of stock) First Alert shows one version on its website: Z-Wave, ZCOMBO-G, Model number 1039833. (Unclear if this is first gen. Model number is different from Amazon's 2nd Gen) Finally, ring's own store has no model number or any other identifier. They all look identical - does not have any differentiating markings, etc., on the face. Does anyone know what the difference is between some of these and if there is indeed a 2nd generation with new capabilities or improved compatibility that is coming (as per Amazon). Thanks.