Patek Philippe 18k Y/G Perpetual Calendar Moonphase B&P 3970J

An 18k yellow gold perpetual calendar moonphase chronograph gents wristwatch, silver dial with index batons, manual wind chronograph movement, sapphire glass, brown leather strap with an 18k yellow gold pin buckle,3 0\'clock sub dial showsleap year cycle and 30 minute chronograph totalizer, 6 0\'clock, sub dial shows moonphase and date, 9 0\'clock sub dial shows constant seconds and 24 hour time, day and month apertures at 12 0\'clock, in excellent condition, last serviced by Patek in March 2008, comes with an original box,an extra 18kyellow gold deployant claspand papers dated April 1989.This is a second series watch with the solid screwed back.