Bosch 3/8" x 18" Installer Drill Bit $6.54 + Free Shipping w/ Prime or on $35+

Amazon [amazon.com] has Bosch 3/8" x 18" Installer Drill Bit for $6.54. Shipping is free w/ Prime or on $25+ or $35+ orders (minimum requirement varies by location).

Home Depot [homedepot.com] has Bosch 3/8" x 18" Installer Drill Bit for $6.63. Shipping is free.