Professional SDS MAX Concrete Hole Saw Electric Hollow Core Drill Bit. Material: 45# steel & YG6. Surface Treatment: Sand Blasting. Suitable For: brick, concrete walls, air conditioning openings Features Made of high quality metal material and with carbide tipped. Rounds alloy blade combinations, each blade to bear part of the workload, not prone to chipping off the edge High-frequency welding technology, welding openings is very strong, smooth inside and outside welding mouth, Precision engage, appearance. Note: Please allow 1-3mm differs due to manual measurement. Due to the different display and different light, the picture may not reflect the actual color of the item. Thanks for your understanding.