Oak Leaf via Amazon offers the Oak Leaf Hair Straightener Brush for $23.99. Coupon code "RVUUZU8N" cuts it to $18.45. Plus, Prime members receive free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $5.48.) That's the lowest total price we could find by $9. It features anti-scald teeth, auto shut-off, and negative ion generation to aid in detangling hair.