FIG. 1 is a front perspective view showing my new design for a thermometer configured to measure the temperature of a btt terminus, FIG. 2 is a top view thereof, FIG. 3 is a bottom view thereof, FIG. 4 is a front view thereof, FIG. 5 is a rear view thereof, FIG. 6 is a right side view thereof, FIG. 7 is a left side view thereof, and, FIG. 8 is an exploded view thereof.