One Hole EMT Pipe Strap 1/2″, Malleable Iron
https://nsiindustries.com/product/one-hole-emt-pipe-strap-1-2-malleable-iron/
Bridgeport One Hole EMT Pipe Straps are used to secure electrical metallic tubing to (EMT) to a variety of mounting surfaces. Malleable iron construction offers the heaviest-duty solution with excellent impact resistance.