Paterson Certified Thermometer - 9" Tweet Description The Paterson Certified Thermometer is a 9" long glass stem thermometer, calibrated and guaranteed accurate to 0.3°C.Featuring dual scale markings in 0.3°C steps from 13 to 30°C and in 0.25°F steps from 56 to 86°F. Accurate temperature readings are essential for optimum processing. Details Additional Category Tags: Developing & Processing, Developing & Processing Supplies, Developing & Processing Accessories Category: Photography Manufacturer Catalog Number: PTP363 Product Manufacturer: Paterson Subcategory: Darkroom Equipment