Product Literature
![Product Literature: ProLine® XE Tankless Non-Condensing (100 series)](https://www.hotwater.com/dw/image/v2/BDTV_PRD/on/demandware.static/-/Sites-hotwater-Library/default/dw846133d9/images/noimagelarge.png?sw=375&sh=375&sm=fit)
Product Literature: ProLine® XE Tankless Non-Condensing (100 series)
The ATO-310 has been discontinued since December 25, 2018 (Source: https://www.supplyhouse.com/AO-Smith-ATO-310U-200-ATO-310U-Tankless-Water-Heater-Natural-Gas)