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PLEXUS CORP. AND SEAMED CORPORATION ANNOUNCE MERGER
Tuesday, March 16, 1999 09:00 PM

        Neenah, WI - March 16, 1999 - Plexus Corp. (Nasdaq: PLXS) and SeaMED
Corporation (Nasdaq: SEMD) announced today that the two companies have entered
into a definitive merger agreement. Each outstanding share of SeaMED common
stock will be converted into 0.4 shares of Plexus common stock, subject to a
minimum per share value for each SeaMED share of $12.00 and a maximum per share
value of $15.00 based on an average closing price of Plexus common stock prior
to the closing of the transaction.

        As a result of the proposed merger, which will be tax-free and accounted
for as a pooling of interests, SeaMED will become a wholly owned subsidiary of
Plexus. The merger is subject to several conditions, including the approval of
SeaMED's shareholders and the expiration of the waiting period under the federal
Hart-Scott-Rodino Antitrust Improvements Act. Plexus expects to take a one-time
charge primarily for merger related expenses at the close of the transaction,
which is expected to occur late in its third or early in its fourth fiscal
quarter of 1999, and it expects the transition to be accretive in fiscal 2000.

        "The merger with SeaMED is an important component of our strategy to
accelerate growth and create value for shareholders," said Pete Strandwitz,
Chairman and Chief Executive Officer of Plexus. "We believe there is an
exceptional strategic fit relative to Plexus' business model and leading
engineering capabilities. This merger also supports Plexus' geographic expansion
plan."

        "Key to the merger is the compatibility of our cultures and a mutual
philosophy focused on service, quality and integrity," added John Nussbaum,
President and Chief Operating Officer of Plexus. "The merger increases our
engineering staff by 50% to over 300, and will provide many new opportunities
with current and potential customers. The merger strengthens our niche in the
medical market, enhances our ability to design more complex products, and brings
us higher level assembly capabilities in both the medical and non-medical
markets."

        "The combination of Plexus and SeaMED creates a powerhouse in contract
engineering and manufacturing for both commercial and medical technology," said
Bob Berg, President and CEO of SeaMED Corporation. The merger will provide a
stronger financial and operational foundation to offer our high level of
engineering, regulatory and manufacturing expertise to a wider range of
customers and for increasingly larger and more complex projects. This is a great
step forward for our employees, customers and shareholders."

        Upon completion of the merger, SeaMED is expected to continue to operate
as a division of Plexus without significant impact on the duties of its current
management and employees. Mr. Berg and Ed Rampy, Chief Financial Officer of
SeaMED, will focus on the integration of the two companies and combined business
development activities.

        Separately, SeaMED today made an announcement regarding its expectations
for SeaMED's quarter ending March 31, 1999.

ABOUT SEAMED


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        SeaMED Corporation designs and manufactures advanced electronic
instruments for medical and commercial technology companies. With its
combination of engineering, manufacturing and regulatory expertise, the Company
assists its customers in developing and commercializing their complex products.
SeaMED is headquartered in Redmond, Washington and has approximately 480
employees.

ABOUT PLEXUS

        Headquartered in Neenah, Wisconsin, Plexus provides product realization
services to original equipment manufacturers (OEMs) in the computer, medical,
industrial, telecommunications, and transportation electronics industries. The
Company offers product development and design services, material procurement and
management, prototyping, assembly, testing, manufacturing, final system box
build and distribution.

        The statements contained in this release which are not historical facts
(such as statements in the future tense and statements including "believe,"
"intend," "anticipate" and similar concepts) are forward-looking statements that
involve risks and uncertainties, including, but not limited to, the level of
overall growth in the electronics industry, the Company's ability to integrate
acquired operations, the Company's ability to secure new customers and maintain
its current customer base, the results of cost reduction efforts, material cost
fluctuations and the adequate availability of components and related parts for
production, the effect of changes in average selling prices, the risk of
customer delays or cancellations in both on-going and new programs, the effect
of start-up costs of new programs and facilities, the effect of economic
conditions, the impact of increased competition and other risks detailed in the
Company's Securities and Exchange Commission filings.