Is the Atlantis 275 good enough as a boat's only radio?

For kayaks, dinghies and short coastal trips, yes. For offshore or long-range communication, a fixed-mount 25 W VHF with a tall antenna reaches much farther.

Does it really float?

Yes. Uniden rates it to float face-up and survive submersion, which is the main reason paddlers and small-boat crews pick it over cheaper handhelds.

Does it receive NOAA weather channels?

Yes. It tunes NOAA weather channels and can sound an alert for severe weather warnings.

Can it call for help with DSC?

No. It has no DSC button or GPS, so it cannot send a digital distress call. You would hail on channel 16 by voice.

The radio, a rechargeable battery pack, an antenna, a belt clip and a charging cradle with adapter. Check the listing for the exact bundle.

How does it compare with the Atlantis 270?

The 275 is the floating, submersible version of the same handheld family. If you never go near the water's edge, the non-floating model is lighter, but the float rating is worth it on small craft.