Quick “Clip-On, Clip-Off” design. Compass and thermometer are cushion-mounted. Compass is luminous and liquid-filled. Thermometer is liquid-filled. Freeze warning and heat warning zones. Thermometer reads down to a chilly -20° F or -30° C. Accurate to 2° C Dimensions: 2.25" W x 1.4" H x 1.2" D (5.8 cm x 3.5 cm x 3.0 cm) Weight: 0.8 oz (23 g)