If your Sleep Number mattress no longer holds air or adjusts firmness, the fix usually comes down to one of two parts: the pump that inflates and controls the mattress, or the chamber that actually holds the air. The Select Comfort Sleep Number Air Bed Pump for Queen/King Mattresses (Model NXT03DR) and the Select Comfort Sleep Number S 276 Twin XL Air Mattress Chamber tackle those two different jobs. Picking the right one starts with knowing which component is failing.
Quick verdict
The NXT03DR Air Bed Pump is the full inflation-control unit, and the S 276 Twin XL Air Chamber is the inflatable bladder for a split-king setup. The pump suits a broken inflation system; the chamber suits a leaking bladder.
At a glance
| Product | Listed Price | Price Bar | Key Details |
|---|---|---|---|
| Select Comfort Sleep Number Air Bed Pump For Queen King Mattress Model NXT03DR | USD 324.99 | Wireless remote, two hoses, dual-chamber control | |
| Select Comfort Sleep Number S 276 TWIN-XI Air Mattress Chamber (1/2 King) | USD 99.99 | Twin XL size, tested to hold air, adjustable firmness |
Where each product wins
The NXT03DR pump wins when the mattress fails to inflate or adjust; it restores independent control of each side. The S 276 Twin XL chamber wins when the pump works but one side of the bed deflates; the chamber replaces the part that holds the air.
Product notes
Select Comfort Sleep Number Air Bed Pump For Queen King Mattress Model NXT03DR
This used pump is a full air-control replacement for a queen or king Sleep Number bed. It comes with a wireless remote, two hoses, and a power cord, letting you adjust firmness on the left and right sides independently. The beige unit lists built-in pump and dual-chamber as its core features, so it covers the inflation duties of the mattress system. A reason to buy: if the pump is the part that stopped working, this bundle gives you everything needed to restore control, and the 2-year warranty plus trade-in option add some peace of mind. A limitation to keep in mind: at $324.99, it won't help if a chamber leak is the actual problem. The unit is used and does not come with Sleep Number services or warranties.
Select Comfort Sleep Number S 276 TWIN-XI Air Mattress Chamber
This used chamber is sized as a Twin XL, also referred to as 1/2 King in the title, making it a match for split-king beds. It is a functional replacement for a chamber that has developed a leak; the unit has been tested to hold air and no leaks were detected. It also carries adjustable firmness and inflatable features, which aligns with the chamber's role in the Sleep Number system. A reason to buy: if your pump is working but the mattress deflates, this $99.99 chamber replaces the specific leaking part without paying for a whole setup. A limitation to weigh: it is only one chamber, so a full king bed would need two of these, and the package does not include a pump to inflate it.
Final choice by use case
If you already know the pump is dead, the NXT03DR pump is the part to order. If the chamber is leaking, the S 276 chamber is the direct replacement. If you're not sure, check whether the pump runs and whether the leak is in the bladder before spending.
