What thermal printer are these compatible with?

The RL2765DT is a 1.75" x 1.25" direct thermal label on a 1" core with a 4" outer diameter. It has been tested with Zebra brand direct thermal printer models that take 1" cores. If shopping for another printer brand, you'll want to review the printer model's specifications. If you need direct assistance with finding the right product for your printer, you're welcome to reach out to Customer Support at 888-575-2235.

will these work on a dymo labelwriter 450?

The RL2765TW is not a DYMO compatible product. However, we do offer several products that can be used in DYMO brand printers. I have included a link below for your review. https://www.onlinelabels.com/comparable/dy-labels

Is this compatible with the Star 700 or Star TSP100?

We have not tested the Star TSP100 printer with our roll products. The RL2765RT is a 1.75" x 1.25" removable thermal transfer label on a 1" core with a 4" outer diameter. It features a 0.125" (1/8") gap between labels for Gap Sensing. We'd recommend checking with your printer manufacturer to make sure this product meets the specifications of the printer.