28mm / 1-1/10 inch Metal Steel Hole Saw Drill Bit, Metal Hole Cutter for Thick Metal,Stainless Steel,Iron and Wood (28mm / 1-1/10 inch): Amazon.com: Tools & Home Improvement
4 in. Bi-Metal Hole Saw
Drill America 1-5/8-in Carbide-tipped Arbored Hole Saw with Hard Case in the Hole Saws & Kits department at Lowes.com
HOLE SAW TCT 45MM - 1 3/4" - TCT HOLESAW FOR METAL | Fowkes Bros
Bi-Metal Hole Saws | KW04 Model | K&W Tools Co., Ltd. - Manufacturing Metal Tool Specialist in Taiwan