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                                                             Executed in 6 Parts
                                                           Counterpart No. (   )


                              NATIONAL EQUITY TRUST


                          TOP TEN PORTFOLIO SERIES 211


                            REFERENCE TRUST AGREEMENT


         This Reference Trust Agreement dated January 12, 2000 among Prudential
Securities Incorporated, as Depositor and The Chase Manhattan Bank, as Trustee,
sets forth certain provisions in full and incorporates other provisions by
reference to the document entitled "National Equity Trust Low Five Portfolio
Series, Trust Indenture and Agreement" (the "Basic Agreement") dated April 25,
1995. Such provisions as are set forth in full herein and such provisions as are
incorporated by reference constitute a single instrument (the "Indenture").

                                WITNESSETH THAT:


         In consideration of the premises and of the mutual agreements herein
contained, the Depositor and the Trustee agree as follows:

                                     Part I.


                     STANDARD TERMS AND CONDITIONS OF TRUST


         Subject to the provisions of Part II hereof, all the provisions
contained in the Basic Agreement are herein incorporated by reference in their
entirety and shall be deemed to be a part of this instrument as fully and to the
same extent as though said provisions had been set forth in full in this
instrument except that the Basic Agreement is hereby amended in the following
manner:



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A.       Article I, entitled "Definitions", paragraph 22, shall be amended as
         follows:

         "Trustee shall mean The Chase Manhattan Bank
         or any successor trustee appointed as
         hereinafter provided."

B.       Article II, entitled "Deposit of Securities; Acceptance of Trust",
         shall be amended as follows:

         The second sentence of Section 2.03 Issue of Units shall be amended by
         deleting the words "on any day on which the Depositor is the only Unit
         Holder."

C.       Article III, entitled "Administration of Trust", shall be amended as
         follows:


         (i)      Section 3.01 Initial Costs shall be amended to substitute the
                  following language:


                  Section 3.01. Initial Cost The costs of organizing the Trust
                  and sale of the Trust Units shall, to the extent of the
                  expenses reimbursable to the Depositor provided below, be
                  borne by the Unit Holders, provided, however, that, to the
                  extent all of such costs are not borne by Unit Holders, the
                  amount of such costs not borne by Unit Holders shall be borne
                  by the Depositor and, provided further, however, that the
                  liability on the part of the Depositor under this section
                  shall not include any fees or other expenses incurred in
                  connection with the administration of the Trust subsequent to
                  the deposit referred to in Section 2.01. Upon notification
                  from the Depositor that the primary offering period is
                  concluded, the Trustee shall withdraw from the Account or
                  Accounts specified in the Prospectus or, if no Account is
                  therein specified, from the Principal Account, and pay to the
                  Depositor the Depositor's reimbursable expenses of organizing
                  the Trust and sale of the Trust Units in an amount certified
                  to the Trustee by the Depositor. If the balance of the
                  Principal Account is insufficient to make such withdrawal, the
                  Trustee shall, as directed by the Depositor, sell Securities
                  identified by the



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                  Depositor, or distribute to the Depositor Securities having a
                  value, as determined under Section 4.01 as of the date of
                  distribution, sufficient for such reimbursement. The
                  reimbursement provided for in this section shall be for the
                  account of the Unitholders of record at the conclusion of the
                  primary offering period and shall not be reflected in the
                  computation of the Unit Value prior thereto. As used herein,
                  the Depositor's reimbursable expenses of organizing the Trust
                  and sale of the Trust Units shall include the cost of the
                  initial preparation and typesetting of the registration
                  statement, prospectuses (including preliminary prospectuses),
                  the indenture, and other documents relating to the Trust, SEC
                  and state blue sky registration fees, the cost of the initial
                  valuation of the portfolio and audit of the Trust, the initial
                  fees and expenses of the Trustee, and legal and other
                  out-of-pocket expenses related thereto, but not including the
                  expenses incurred in the printing of preliminary prospectuses
                  and prospectuses, expenses incurred in the preparation and
                  printing of brochures and other advertising materials and any
                  other selling expenses. Any cash which the Depositor has
                  identified as to be used for reimbursement of expenses
                  pursuant to this Section shall be reserved by the Trustee for
                  such purpose and shall not be subject to distribution or,
                  unless the Depositor otherwise directs, used for payment of
                  redemptions in excess of the per-Unit amount allocable to
                  Units tendered for redemption. As directed by the Depositor,
                  the Trustee will advance funds to the Trust in an amount
                  necessary to reimburse the Depositor pursuant to this Section
                  and shall recover such advance from the sale or sales of
                  Securities at such time as the Depositor shall direct, but in
                  no event later than the termination of the Trust. Repayment of
                  any such advance shall be secured by a lien on the assets of
                  the Trust prior to the interest of the Unit Holders as
                  provided in Section 6.04.


         (ii)     The third paragraph of Section 3.05 Distribution shall be
                  amended to add the following sentence at the end thereof:

                  "The Trustee shall make a special distribution of the cash
                  balance in the Income and Principal accounts available for
                  such distribution to Unit



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                  Holders of record on such dates as the Depositor shall
                  direct."

         (iii)    The second to the last paragraph of Section 3.08 Sale of
                  Securities shall be amended to replace the word "equal" with
                  the following phrase: "be sufficient to pay."



D.       Reference to United States Trust Company of New York in its capacity as
         Trustee is replaced by the Chase Manhattan Bank throughout the Basic
         Agreement.


                                    Part II.


                      SPECIAL TERMS AND CONDITIONS OF TRUST


         The following special terms and conditions are hereby agreed to:

         A. The Trust is denominated National Equity Trust, Top Ten Portfolio
Series 211.

         B. The Units of the Trust shall be subject to a deferred sales charge.

         C. The contracts for the purchase of common stock listed in Schedule A
hereto are those which, subject to the terms of this Indenture, have been or are
to be deposited in Trust under this Indenture as of the date hereof.

         D. The term "Depositor" shall mean Prudential Securities Incorporated.

         E. The aggregate number of Units referred to in Sections 2.03 and 9.01
of the Basic Agreement is 250,000 as of the date hereof.

         F. A Unit of the Trust is hereby declared initially equal to
1/250,000th of the Trust.

         G. The term "First Settlement Date" shall mean January 19, 2000.

         H. The terms "Computation Day" and "Record Date" shall mean quarterly
on the tenth day of March, June, September, and December commencing March 10,
2000.



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         I. The term "Distribution Date" shall mean quarterly on the
twenty-fifth day of March, June, September, and December commencing March 25,
2000 or as soon thereafter as possible.

         J. The term "Termination Date" shall mean January 16, 2002.

         K. The Trustee's Annual Fee shall be $.95 (per 1,000 Units) for
100,000,000 and above units outstanding; $1.01 (per 1,000 Units) for
50,000,000 - 99,999,999 units outstanding; $1.05 (per 1,000 Units) for
49,999,999 and below units outstanding. In calculating the Trustee's annual fee,
the fee applicable to the number of units outstanding shall apply to all units
outstanding.

         L. The Depositor's Portfolio supervisory service fee shall be $.25 per
1,000 Units.

               [Signatures and acknowledgments on separate pages]



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         The Schedule of Portfolio Securities in Part A of the prospectus
         included in this Registration Statement for National Equity Trust, Top
         Ten Portfolio Series 211 is hereby incorporated by reference herein as
         Schedule A hereto.