Basal Thermometers All the thermometers you will need for BBT charting. We currently offer a regular and a clinical-grade Basal Body Thermometer. All of our Digital Fertility Thermometers are supplied with BBT instructions & BBT chart. Basal Ovulation Thermometer and Free BBT Chart £5.99Add to basket Basal Ovulation Thermometer – Bundle 1 £11.79 £9.99Add to basket Sale Basal Ovulation Thermometer – Bundle 2 £14.99 £12.99Add to basket Sale Digital Basal Thermometer – Clinical Grade £19.99 £17.99Add to basket Sale