Guardian Drain Lock

How to Measure

Choosing the correct Guardian Drain Lock® starts with measuring the actual drain opening—not relying only on the nominal pipe size. Drain size labels and actual openings are not always the same.

How to measure your drain

  1. Remove any loose basket or strainer so you can access the drain opening.
  2. Measure the inside diameter of the opening at its narrowest usable point.
  3. Note whether the opening is round or square and identify the floor drain or floor sink style.
  4. Photograph the opening, surrounding grate, and any manufacturer markings.
  5. Compare the actual measurements with the product specifications before ordering.

Need help choosing the right size?

Email orders@guardian-drainlock.com or call 1-844-564-9216. For faster sizing support, include your measurements and clear photos from above and below the grate when possible.

Lock and Stop Drain Lock installed beneath a square OEM floor drain cover

More locking solutions

Have a floor drain that isn’t compatible with Guardian?

Drain-Net offers an alternative locking solution. We retrofit OEM floor-drain covers with the Lock & Stop Drain Lock, providing tamper-resistant protection for drain sizes and configurations outside the Guardian product range.

Explore Lock & Stop Drain Locks →