Costco Wholesale has for its Members: 9-Ct Oral-B iO Deep Clean Replacement Toothbrush Head on sale for $54.99 – $11 off manufacturer’s savings automatically applied = $43.99. Shipping is $2.99.
Note: Non-Members may purchase but are subject to a 5% surcharge.
Thanks to Community Member wileysmiley for sharing this deal.

About this product:
9-count Replacement Toothbrush Heads
Only Compatible with Oral-B iO Electric Toothbrush Handles
Soft & Dense Bristles
Angled Bristles For Plaque Removal