Flag Blocks 1.IMPA CODE:371586-371588 2.Cast brass flag line blocks covered by a semi-circle guard with an eye on top. Flag Blocks Impa Code : 37 15 86 - 37 15 88 1.Cast brass flag line blocks covered by a semi-circle guard with an eye on top.2.Impa Code:371586 Flag block, brass,32 mm Impa Code:371587 Flag block, brass,38 mm Impa Code:371588 Flag block, brass,50 mm