Duct probe -30 to 120°C$299.00 For Testo 6651. Call for changes in filter, cable and probe Call us for a quote Product Model: 0555 6603 Duct probe -30 to 120°C quantity Add to cart SKU: 0555 6603 Category: Testo Sensors Parts & Accessories Tag: Testo Sensors Parts & Accessories Description Description For Testo 6651. Call for changes in filter, cable and probe Related products Testo 340 CO Replacement Sensor (0-10000 ppm H2 compensated)0 out of 5 $835.00 Add to cart SO2 replacement sensor (0-5000 ppm)0 out of 5 $986.00 Add to cart Testo 340 CO Replacement Sensor (Low Range)(0-500 ppm)0 out of 5 $795.00 Add to cart