VEVOR Outdoor Stair Railing, Alloy Metal Hand Railing, Fit 1 or 2 Steps Flexible Transitional Handrail, Outdoor Stair Rail W/ Installation Kit, Step Handrail for Concrete or Wooden Stairs, Silver

What size bit to use for drilling into concrete for the anchor bolts?

I want railing for 1 step 7-1/2" high, posts 12" to 15" apart OR there is another step 3-1/2" (same steps & porch) so low to high 13" and posts 15" to 18" apart. Black. Alloy or steel or iron to support 225 lbs or more. Your SS YJH-00016 is seeseems great