3 1/2" Flat Bronze Concrete Survey Marker
"C" style (US Army Corps of Engineers Type 1 Disc) has the classic 3" (76mm) long split-style tapered stem. It is available in 3-1/2" (89mm) or 4" (102mm) diameters. Orbital formed from solid unleaded silicon bronze bar.
The CAPMAG ceramic magnet can be used with these concrete markers to assure easy detection of the mark with a magnetic locator up to 6 to 12 inches deep, depending on soil conditions.
C35FB Concrete Marker Installation Instructions