SDS drill bits are standard for use in most power drills. Most hand drill systems also accept SDS drill bits. Our SDS bits are carbide tipped and can be re-sharpened. Be aware that as your SDS drill bits wear down the "shoulders" wear also. This can make the hole you are drilling slightly smaller. Don’t be afraid to manipulate your drill to enlarge the hole a little bit. Enlarging the start of the hole creates a slight taper allowing the bolt to slide in easier. This is especially relevant in extremely hard stone.