Hi Steven,
Thank you for your question. They do not come with screws, but we recommend: For STEEL stairs, using a hardened steel ¼” x 1” Phillips Flat Head Self-tapping Floor Screw. Pilot hole is 13/64”. If you find the self-tapping screws are very hard to drive in, you may use a larger drill bit (7/32”) for your pilot holes, but be careful not to strip treads. For WOOD stairs, we recommend a ¼” x 1 ¼” Stainless Steel Wood Screws. Drill pilot holes with a 3/16” drill, at least the depth of the anchor.
Thank you,
The Koffler Team