Replacing a Sleep Number chamber is not a one-size-fits-all purchase. The two used options here are the California King 275 at $159.99 and the Twin XL S 276 half-king chamber at $99.99. Both are made by Sleep Number in the US and both use inflatable construction, so your decision comes down to bed size first and price second.
Quick verdict
Pick by bed size first: the larger chamber matches a Cal King platform, while the compact half-king chamber is for a Twin XL side. If both sizes apply, the price gap favors the smaller one.
At a glance
| Product | Listed price | Size | Attribute bar |
|---|---|---|---|
| Select Comfort Sleep Number Cal. King Air Bed Chamber 275 Mattress - Tested Good | $159.99 | California King | |
| Select Comfort Sleep Number S 276 TWIN-XI Air Mattress Chamber (1/2 King | $99.99 | Twin XL (1/2 King) |
Where each product wins
The 275 wins when you're replacing a full California King and want the 6-inch thickness and Tested Good label. The S 276 wins when you're outfitting a half-king side and want the lower-priced option.
Product notes
Select Comfort Sleep Number Cal. King Air Bed Chamber 275 Mattress - Tested Good
This is the larger of the two chambers here. It is a used, beige Sleep Number unit with inflatable construction and US manufacturing. The listed specs include a 6-inch thickness, and the title carries the Tested Good label. It's the higher-priced of the pair, and that extra cost buys a chamber designed for a Cal King footprint. The limitation is the price, not the build: when your bed is already Cal King, the 275 is the direct replacement, but you'll pay more than for the half-king chamber.
Select Comfort Sleep Number S 276 TWIN-XI Air Mattress Chamber (1/2 King
This is the more compact chamber, sized as a Twin XL and labeled a 1/2 King. It is a used, off-white Sleep Number unit with inflatable construction and adjustable firmness. The unit is described as fully tested and able to hold air for days with no leaks detected. The lower price makes it the wallet-friendlier choice, but the footprint is narrower: it serves a Twin XL side, not a full Cal King bed. If your setup uses half-king halves, this is the cheaper replacement.
Final choice by use case
If your bed frame is set up for the larger chamber, choose the 275. If you're working with a Twin XL or half-king side, choose the S 276. When the listed price is the deciding factor, the S 276 is the one that costs less, as long as the bed size matches.
