Follow these simple steps: Turn your instrument head counterclockwise to unscrew it from the power handle Remove the lamp from the base of the instrument head by pulling it straight out Insert the replacement lamp by pushing it straight into the base of the instrument head Reattach your instrument head to the power handle by turning clockwise and screwing it into place Note: This procedure is for all Welch Allyn otoscopes and ophthalmoscopes except the Welch Allyn pocket scopes. For these, the lamp is located in the throat illuminator piece, below the instrument head.