I have a limited number of NOS/unused 1960's 'Omega Chronographs Directions for use' booklets which give detailed instructions on using the chronograph pushers, dial and various outer scales found on the Speedmaster etc.. This style booklet was in use at least between 1964 and 1969. I recently sold one on ebay for £155 plus shipping but OF members can have one for £125 including worldwide shipping.