We are offering waterproof ph tester, technical data: range: ph: -2-16.00; orp: ±1000mv conductivity: 0-2000us; 2.00-20.00ms tds: 0-1300ppm, 1.30-13.00ppt salt: 0-1000ppm; 1.00-12.00ppt temperature: 0-90°c accuracy: ph:±0.01+1digit; orp:±2+ 1digit conductivity, tds, salt:â±2% f.s. Temp: â±0.2â°c + 1digit resolution: ph: 0.01; orp: 1; cond.: 1us0.01ms; tds: 1ppm0.01ppt; salt: 1ppm0.01ppt; temp: 0.1c atc: ph: 0-90°c; condtdssalt: 0-50°c power: dc1.5v x 4 battery size: aaaum-4