This viscometer is extremely easy to use, first fill the tube with sample, then invert tube. The ball moves against a white background with red reference lines making it easy to read. Repeatability with good technique varies from ±0.2 to ±1.0%, depending upon time of descent. Next, restore tube to normal position, turn the knob to release the ball, and then simply measure the time of descent. Falling ball viscometers require a 7-mL sample volume.