2 1/2" luminescent dial with 8" stem. 1/2° gradations. Easy to read Fahrenheit and Centigrade scales. Hermetically sealed, leak proof, will not fog, corrosion resistant stainless steel. Comes with adjustable positioning clamp. Precision accuracy to ± 1/2°. For maintaining absolute accuracy. Hermetically sealed for use with developing tanks and faucet attachments. Use in developing trays.