High Quality NEW!!! Dimensions: 14.4 x 8.2 x 3.81 cm Weight: 18 g Reliable & accurate basal temperature results: ±0.09℉/±0.05℃ Low energy - Pre-installed button battery may last 3-6 months. User friendly - Offers gentle alarm wakeup, indication of the completion of test & up to 365 measurement memory recall. All your data is stored in the cloud, so you don’t have to worry about manually uploading or losing your information. SEAMLESS & SMART - NO Button, NO Screen, you can take a quick measurement effortlessly without manual writing or charting or checking the App. The tracker will seamlessly sync the basal body thermometer to App & do Smart BBT Charting. You can track & view your cycle any time. The iOS & Android based Smart Tracker APPs interpret & chart the body basal temperature (BBT) to predict the conception rate intelligently based on Fertility Awareness Method. Takes 1-3mins to read a basal temperature reading.