I purchased my accessories on Amazon. Desk, mat, ANT+ dongle, had a spare usb extension laying around. Everything was less than $100.00. Here's the desk on which I have my laptop 34" monitor, usb keyboard, and bluetooth speaker. https://www.amazon.com/dp/B09VDFXPDH?psc=1&ref=ppx_yo2ov_dt_b_product_details