A stainless steel flat piece that is used to measure velocity during the test.  The flag bracket mounts to the back of the crosshead on the lower right hand side.  It holds a double-pronged stainless steel flag which is part of the velocity measuring system.  The flag passes through a velocity detector affixed to the accessory mounting  when the drop weight assembly is in motion.  The flag interrupts an infrared light  beam which allows the instantaneous speed of the falling assembly to be determined.  This measurement is usually made just before the tup impacts the specimen.