If you are looking for cockpit instruments that feature cutting edge technology yet are intuitively simple to operate, look no further. The outstanding Clipper range of instruments incorporate technically advanced electronics in an industry standard 110mm square case. Ease of use and display clarity were top of the design brief. All Clipper instruments have giant digits and multilevel backlighting. As with all Nasa instruments - they are excellent value too. Technical Specifications: 40mm high characters Speed (Knots/m.p.h.) Trip Distance (N.Miles / Miles) Total Distance (N.Miles / Miles) Trend indicator shows acceleration / deceleration Selectable speed averaging Tactile keypad Complete with weather cover and paddlewheel unitThis product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns. Specifications: Instrument Function: Speed Box Dimensions: 4"H x 8"W x 10"L WT: 2.1 lbs UPC: 609722871167 Owner&';s Manual (pdf)