This is a nice antique beryllium double end opened end wrench marked &quotAMPCO W699 BERYLLIUM 1/2 - 7/16 U.S.A." on the beryllium. This is an nice "NO SPARK" type wrench, made to be used in applications where no sparking can be allowed to acure. It is 6" long overall, the wrench head are .54" thick. We note a few minor edge dings, otherwise in very good condition. A hard to find heavy duty square opened wrench by a well known quality tool maker!