Everhard MM21034 - Premium Convertible Seam Tester / Seam Probe

The MM21034 Premium Convertible Seam Tester is a versatile, American-made tool designed to give roofing professionals ergonomic comfort and flexibility. Its ability to convert between handheld and stand-up use, combined with a safe seam probe, makes it excellent for installers needing both precision detail and broader seam inspection capabilities.

Key Features

• Dual-purpose functionality—portable handheld test probe or pole‑mounted stand‑up tool for efficient inspection across large membrane areas
• Enhanced comfort & grip with its soft-handle, reducing fatigue during long seam-checks
• Safe membrane testing thanks to the non‑penetrating, blunted tip
• Seamless system compatibility with Everhard’s pole system for hands‑free precision work
• Precision seam inspection around flashings, corners, and welds
• Large-area seam sweeps, using the pole for reduced roof traffic and improved ergonomics
• Situations calling for clean, safe probing with minimized membrane damage risk

Tool type: Handheld seam tester that converts to stand-up use with an extension handle. 

Overall length: 8½″ (approx. 216 mm). 

Probe/shaft: Polished steel, ¼″ diameter with a tapered, 90° bend and blunted tip to avoid gouging membrane. 

Handle: 5″ soft-grip plastic; threaded end.

Convertible feature: Threaded handle accepts Everhard’s 60″ fiberglass extension handle (#MR02400) for stand-up testing.

Weight: 0.35 lb (0.16 kg). 

Country of origin: Made in USA. 

Package quantity: 1. 

UPC: 095412210345.

• Hold the soft-grip handle firmly and bring the seam probe tip to the weld or membrane seam.
• Position the probe so the blunted tip lightly contacts the seam surface under light pressure.
• Slide or trace the probe along the length of the seam to detect voids, cold welds, or defects.
• For extended reach, screw the extension pole into the threaded handle and continue testing from a standing position.
• After inspection, wipe the probe shaft clean and retract from any tight areas.
• Check the handle threads or extension point for debris before reuse.
• Store the tester in a dry location to avoid damage to the probe or handle.

Q: What does the MM21034 do?
A: It’s a premium seam tester for verifying single-ply membrane welds (TPO, PVC, EPDM). The blunted, bent probe helps you detect voids, cold welds, and fishmouths without gouging the membrane.

Q: What makes it “convertible”?
A: The handle is threaded to accept an extension handle (stand-up testing) and can be used handheld for detail areas, corners, and tight spots—switching takes only seconds.

Q: How should I use it for best results?
A: Hold the probe at a shallow angle and apply light, even pressure as you trace the weld. Work steadily along the lap, marking suspect areas for repair instead of forcing the probe.

Q: Any maintenance or safety tips?
A: Wipe off debris after use, keep the shaft straight, don’t sharpen the blunted tip, and store the tool dry. Inspect threads before attaching an extension handle.