what is a 280C

Yes Dogtra BP37T IQ Transmitter Battery is for 280C remote battery.

Is this the correct replacement battery for the dogstra arc tranamitter??

Please see the below link for correct item.

https://www.dogtrainerstore.com/products/dobprebafor2?variant=58843499915

I have an IQ+ and I need a replacement battery for the transmitter, which battery should I order?

For transmitter (Remote) - BP37T   https://www.dogtrainerstore.com/products/dobpiqtrba?variant=58843648907 For receiver (Collar) - BP37F  https://www.dogtrainerstore.com/products/dobprebafore?variant=58843648779