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Representative photo · AO Smith ProLine XE Condensing Outdoor Tankless (ATO-540H) Photo: AO Smith · Exact model appearance may vary. 
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Representative photo · Bradford White Infiniti GS Tankless (Representative same-brand type) 
A.O. Smith · Model ATO-540H-N
Adapt Tankless 199K
High-efficiency condensing tankless with app control.
Specs & features
- 10 GPM flow rate
- Natural gas
- UEF 0.96
- 12-year manufacturer warranty
- Covered by A1 Lifetime Service membership
Best for: new homes
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