Hi @Bobby01 - Thanks for reaching out! We agree with @OldGuyot's suggestions about traditional backpacking ground pads. There are some great options that would work well in your Nemo tent.  If you are looking for one that will take up almost the entire ground area of your tent, the Big Agnes Insulated SLX Tent Floor Sleeping Pad is a good option. 

If you are thinking about using a classic air mattress, those generally only come in standard dimensions: twin (39” x 75”), full (54” x 75”), queen and king. It looks like only a twin size air mattress will fit in the Nemo Hornet Elite, which would leave you with a little bit of space on either side.

If you do plan to use a standard air mattress, know that they do not provide much insulation like the sleeping pads do. If you are going to be camping in colder weather, bringing along a closed-cell foam pad for underneath the air mattress will help.

Let us know if you have any additional questions and we'll be happy to help!

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