The 53077-D Medium Digital Magnetic Centering Head (for pipes 3” and larger) is designed to be hands free up to 24″ so you can establish and mark a center-line at any angle around the circumference (inside and out) on a pipe or tank.
The NEW 53087-D Large Digital Magnetic Centering Head (for pipes 12” and larger) is designed to be hands free so you can establish and mark a center-line at any angle around the circumference (inside and out) on a pipe or tank.