Examples of the type

1996-Apr-02 – (en) Specimen; red overprint "MUESTRA SIN VALOR" on both sides, punch hole cancelled, Red overprint numbered 3 digits on center left bottom.Signatures: MUM, FCS(en) Specimen; red overprint "MUESTRA SIN VALOR" on both sides, punch hole cancelled, Red overprint numbered 3 digits on center left bottom.