Notifiable Interest

Tristel PLC
06 July 2007

                          Tristel PLC ('the Company')

                              Notifiable Interest



A form TR-1 containing the following information has been received by the
Company.

TR-1 notification of major interests in shares

1. Identity of the issuer or the underlying issuer of existing shares to which
voting rights are attached:

Tristel PLC

2. Reason for the notification

DTR disclosure requirements

3. Full name of person(s) subject to the notification obligation:

Peter Stephens

4. Full name of shareholder(s) (if different from 3):

5. Date of the transaction (and date on which the threshold is crossed or
reached if different):

n/a

6. Date on which issuer notified:

06/07/07

7. Threshold(s) that is/are crossed or reached:

> 3%

8. Notified details:

A: Voting rights attached to shares
Class/type of    Situation previous to         Resulting situation after the triggering transaction
shares           Triggering transaction
                                               Notification required under DTR transitional provision 7
if possible
using ISIN CODE  Number of     Number of       Number of  Number of voting       % of voting rights
                 Shares        Voting Rights   shares     rights
                                               Direct     Direct    Indirect     Direct    Indirect

                                               786,954    786,954                3.22%



B: Financial Instruments
Resulting situation after the triggering transaction


Type of financial Expiration date     Exercise/           Number of voting       % of voting rights
instrument                            Conversion Period/  rights that may be
                                      Date                acquired if the
                                                          instrument is
                                                          exercised/ converted




Total (A+B)
Number of voting rights                              % of voting rights


786,954                                              3.22%



9. Chain of controlled undertakings through which the voting rights and/or the
financial instruments are effectively held, if applicable:

N/A

10. Name of the Proxy holder:

n/a

11. Number of voting rights proxy holder will cease to hold:

n/a

12. Date on which proxy holder will cease to hold voting rights:

n/a

13. Additional information:

20,000 shares acquired at a price of 60.5 pence each

14. Contact name:

Contact Peter Stephens

15. Contact telephone number:

0207 4932662




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