You can find this exercise on page 69 of the book Synergistic Golf.
Exercise Type: DB STRENGTH
Exercise Category: SHOULDERS, STRENGTH
Stand with feet hip distance apart holding 3-5-8lb dumbbells in hand with palms facing outer front part of thighs. Inhale to prepare with focus on strong stance and posture. Exhale lifting both arms straight out at a diagonal or V angle (to corners of room) to shoulder height. Inhale return hands to thighs. Repeat lifting sequence 10-20x. If weights get too heavy lift one arm at a time. Do not allow body to sway or move during exercise.