domestic  registered  mail,  but  they  may  be  used  for international registered mail. Sealing All sides of a parcel must be completely sealed (see figure 7-2).  One of the main purposes for registering mail  is  to  provide  security  against  unauthorized openings.  Where flaps are not completely sealed, tape must be used to ensure that no free edge is exposed. Such  tape  must  be  of  a  type  that  can  absorb  an  ink impression, such as paper tape or cloth tape. Clear tape (Scotch   tape)   and   masking   tape   ARE   NOT ACCEPTABLE. The  mailer  must  securely  seal  envelopes. Self-sealing  envelopes  are  not  acceptable  as registered  mail  unless  sealed  with  paper  tape  (see figure 7-3).   Envelopes of strong construction may be   accepted   for   mailing   as   long   as   they   are completely sealed.  Envelopes sold by the USPS are ideally suited for registration.  If tape is used to seal the flaps of letter-size envelopes, the tape must not be placed over the intersections of the flaps.  A space on  each  side  of  the  intersecting  flaps  must  be  left open for postmarks. Packaging All  articles  presented  for  registration  must  be packaged following the procedures in chapter 3 of this training manual and Module C of the DMM.   As the accepting clerk, you may refuse to accept an article if you determine that it is not packaged in a manner that will assure safe transmission in the mails.  The mailer must also tell you whether or not the item is fragile. When it is of a fragile nature, the mailer must describe the interior packaging. WINDOW ENVELOPES Window envelopes that do not have a panel over the opening cannot be used for registered mail.   If a transparent panel is glued to the envelope, the envelope may  only  contain  matter  of  no  intrinsic  value.   The 7-2 KIND OF MAIL MATTER VALUE TO BE DECLARED Negotiable  Instruments- Instruments   payable   to bearer,  including  stock certificates  endorsed  in blank. Market  value.  (All  values are based on the value at the time of mailing.) Nonnegotiable  Instruments- All    registered    bonds, warehouse receipts, checks, drafts, deeds, wills, abstracts,   and   similar documents.  Certificates  of stock are considered nonnegotiable   so   far   as declaration   of   value   is concerned  unless  they  are endorsed in blank. No  value,  or  replacement cost   if   postal   insurance coverage  is  desired.  (See note below) Money Full Value Jewelry,  Gems,  Precious metals. Market value or cost Merchandise Market value or cost Nonvaluables-matter   not having  intrinsic  value  such as letters, files, records, etc. No  value,  or  replacement cost   if   postal   insurance coverage  is  desired.  (SEE NOTE BELOW) Note: Mailers who do not know replacement costs should contact a person or firm familiar with such documents and determine replacement costs before the articles are mailed. Figure 7-1.—A guide for declaring the value of articles to be registered. PCf0702 DATE DATE Figure 7-2.—A parcel showing placement of the APDS for sealing.