The venus compass, 5 degree card measures 5 3/4"(card diameter) x 6"(cutout diameter) and weighs 6.75 lbs(compass) and 4 lbs(cylinder). The compass features: full spherical construction with internal gimbal system, balanced for use in northern and southern hemispheres, the accuracy of indicationis less than or equal to 1 degree, the lag erroris less than or equal to 2 degree, the oscillation period is greater than or equal to 4.7 sec., values exceed the ISO norm (International Organization of Standards), temperature range is -22 F to 158 F, corresponds with the ISO norm for commercial shipping, vibration resistance exceeds requirements of BSH (German Hydrographic Institute), seawater resistant, light alloy housing, dished card with 1 degree graduation, red dazzle-free illumination for 12 volt, super-strong glass dome is insensitive to ultraviolet rays and is guaranteed for life against cracking, crazing and yellowing under normal use, oscillation-free double bottom compensates volume changes in compass fluid, accuracy at all angles of heel insured by full internal gimbal system. Three year warranty on body.