Thumb Score: +23

Amazon [amazon.com] has 4-Pack Philips Sonicare C3 Premium Plaque Control Toothbrush Heads (Black, HX9044/95) for $21.99 – 15% when you ‘clip’ the coupon on product page – 5% when you check out via Subscribe & Save = $17.59.
Shipping is free with Prime or on $35+ orders.

Savings
Save an extra 15% on your first Subscribe and Save order. (check and activate [amazon.com])