10 brushes for $15, these work great!

Aoremon Replacement Toothbrush Heads for Philips Sonicare DiamondClean, Black, Pack of 10 https://www.amazon.com/dp/B08QRV27JK/ref=cm_sw_r_cp_api_i_Z4ZMMF6G1P1T55BSQNNC?_encoding=UTF8&psc=1