Knobs, seals, fasteners, and hardware for Geotech ET and ETL water level meters — the small parts that go missing in the field or wear out long before the instrument does. Item numbers below refer to the ET and ETL repair diagrams in the user manual.

Probe seals

• O-Ring, Buna-N — PFAS-free (item 12). Seals the 5/8" probe body. Replace it whenever you open a probe; a tired O-ring lets water in and causes false or erratic triggering.
• Wave Washer (item 13). Maintains contact pressure inside the probe stack.
• Spiral Retaining Ring, stainless. Retains the probe internals.

Frame and reel hardware

• Sensitivity Knob (item 14) — the indicating knob on the control assembly.
• Clamping Knob, knurled (item 7) — pairs with the brake screw below.
• Brake Screw (item 8) and Clamping Nut, nylon (item 9).
• Reel Knob, phenolic (item 10) and Reel Knob Bolt (item 11) — the reel hand grip and its stripper bolt.
• Frame Handle Grip, vinyl (item 15) — the black grip on the carry handle.
• Screw, 6-32 × 3/8" stainless — general assembly fastener.

ETL rewind hardware

• Camlock Brake, hand reel — the reel brake on ETL frames.
• Manual Crank Handle — with hardware, for manual rewind reels.

Doing a full probe rebuild? Order the probe assembly and grab the O-ring and wave washer at the same time.

Browse all Geotech WLM parts & accessories, or contact us with a photo if you're not sure what a part is called.