Hanperal 65mm SDS Plus Shank Hole Saw Cutter Concrete Cement Stone Wall Drill Bit (Amazon Affiliate)
US: https://amzn.to/2KKDPex
UK: https://amzn.to/2NqfxZI
CA: https://amzn.to/383mNT0
AU: https://amzn.to/2Zwt8DX
5/16″ SDS bit long: https://amzn.to/2Z6wafQ (Amazon Affiliate)
1/4″ SDS bits: https://amzn.to/31KpaHj (Amazon Affiliate)