About this item WHAT YOU WILL GET--1x 100mm/4" Concrete Hole Saw,1x 200mm round handle,2x Center positioning drill bit,1x positioning drill screw.1x Wrench DURABLE MATERIALS---Made of high-quality steel and tungsten,high-frequency welding technology,smooth inside and outside welding mouth,very durable and fast perforated UPGRADED DESIGN--Upgraded high-strength tungsten alloy teeth,longer life,durable,male thread adapter design,match your drill chuck fastening and much more improve speedier drilling. VERSATILE USE---It can be used to open self leveling concrete,hollow brick,cement wall,concrete wall,red brick etc.when installing air conditioners,water pipes,water heaters,fume pipes,etc. QUALITY SERVICE--For use below 100mm: 7A -9A SDS plus rotary hammer drill,For use above 100mm: 9A -13A SDS plus rotary hammer drill,We promise provide you satisfied after sale service,if there is any problem,Please contact us directly,we will refund you full payment or send you a new replacement.