Fluke Infrared Thermometer FLUKE 561 Size: 40–535 (FLUKE 561) Specification — CDRQ2BS10 180 Torque Extension Bar Set Specification — CDRQ2BS10 180 Item # Description Spreading Capacity Throat Depth 212 1875 1964717 6" (15 cm) MD Bar Clamp Spreader 7 7 8" 13 3 8" (200 mm 340 mm) 3 3 16" (81 mm) 212 1884 1964718 12" (30 cm) MD Bar Clamp Spreader 7 7 8" 19 3 8" (200 mm 590 mm) 3 3 16" (81 mm) 212 1893 1964719 18" (45 cm) MD Bar Clamp Spreader 7 7 8" 25 3 8" (200 mm 645 mm) 3 3 16" (81 mm) 212 1909 1964720 24" (60 cm) MD Bar Clamp Spreader 7 7 8" 31 3 8" (200 mm 795 mm) 3 3 16" (81 mm) 212 1918 1964741 36" (91 cm) MD Bar Clamp Spreader 7 7 8" 43 3 8" (200 mm 1120mm) 3 3 16" (81 mm) 40–800 (FLUKE 568) Distance to spot ratio decides how far you can stand and still read the target