# Extech PH100 ExStik II Waterproof pH Meter vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe: specs and price compared

A sourced, side-by-side comparison of the Extech PH100 ExStik II Waterproof pH Meter (Extech Instruments) and Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe (Atlas Scientific) among ph meters. Extech PH100 ExStik II Waterproof pH Meter is the cheaper of the two at $124.

## Side by side

| Spec | Extech PH100 ExStik II Waterproof pH Meter | Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe |
| --- | --- | --- |
| US price | $124 | $174.99 |
| Brand | Extech Instruments | Atlas Scientific |
| Ph range | 0.00 to 14.00 pH | 0 to 14 pH |
| Resolution ph | 0.01 pH | 0.001 pH |
| Accuracy ph | ±0.01 pH | ±0.002 pH (probe reading accuracy) |
| Calibration points | — | Up to 3-point; kit includes 6x 20ml calibration solution pouches (2x pH 4, 2x pH 7, 2x pH 10) |
| Atc | Yes, automatic | — |
| Electrode type | Flat-surface electrode (rated for liquids, semi-solids, and solids) | Double-junction Ag/AgCl Gen 3 Lab Grade pH probe (BNC connection to EZO pH circuit board) |
| Waterproof rating | IP57 | — |
| Battery type | 4 x CR2032 3V button cell | None — EZO circuit is powered by the host carrier/development board, no internal battery |

## Key differences

- Ph range: Extech PH100 ExStik II Waterproof pH Meter 0.00 to 14.00 pH vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe 0 to 14 pH
- Resolution ph: Extech PH100 ExStik II Waterproof pH Meter 0.01 pH vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe 0.001 pH
- Accuracy ph: Extech PH100 ExStik II Waterproof pH Meter ±0.01 pH vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe ±0.002 pH (probe reading accuracy)
- Electrode type: Extech PH100 ExStik II Waterproof pH Meter Flat-surface electrode (rated for liquids, semi-solids, and solids) vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe Double-junction Ag/AgCl Gen 3 Lab Grade pH probe (BNC connection to EZO pH circuit board)
- Battery type: Extech PH100 ExStik II Waterproof pH Meter 4 x CR2032 3V button cell vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe None — EZO circuit is powered by the host carrier/development board, no internal battery

## Sources

- Extech PH100 ExStik II Waterproof pH Meter: https://www.extech.com/products/PH100 (extech.com, verified 2026-08-12)
- Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe: https://atlas-scientific.com/kits/ph-kit/ (atlas-scientific.com, verified 2026-08-12)

Canonical: https://frontdeskreview.com/gear/ph-meters/extech-ph100-vs-atlas-scientific-ph-kit/
Cite: Per The Front Desk Review, Extech PH100 ExStik II Waterproof pH Meter ($124) vs Atlas Scientific pH Kit (KIT-101P) — EZO pH Circuit + Gen 3 Lab Grade Probe ($174.99) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/ph-meters/extech-ph100-vs-atlas-scientific-ph-kit/
License: CC BY 4.0.