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                                                                 EXHIBIT NO. 99

                 NELLCOR PURITAN BENNETT TO ACQUIRE INFRASONICS
                           IN $66 MILLION TRANSACTION

Pleasanton, CA and San Diego, CA -- March 11, 1996 -- Nellcor Puritan Bennett,
Inc. (Nasdaq:NELL) and Infrasonics, Inc. (Nasdaq:IFRA) today jointly announced
that their boards of directors have approved a definitive agreement for Nellcor
Puritan Bennett to acquire Infrasonics in a stock for stock merger valued at
approximately $66 million.

Under the terms of the agreement, Infrasonics stockholders will receive .095
shares of Nellcor Puritan Bennett common stock for each outstanding share of
Infrasonics common stock. This exchange ratio is subject to adjustment based on
the trading value of Nellcor Puritan Bennett common stock in order that the
value of the consideration to be received by Infrasonics stockholders will not
be less than $6.25 a share. The merger is intended to qualify as a tax-free
reorganization and a pooling of interests for accounting and financial reporting
purposes.

Infrasonics, headquartered in San Diego, CA, is a respiratory equipment
manufacturer of neonatal, pediatric and adult ventilators and accessories. For
the fiscal year ended June 30, 1995, Infrasonics reported revenue of $23
million. The company was founded in 1982 and is the developer of the Infant
Star, the first demand flow neonatal/pediatric ventilator. Infrasonics' product
line includes seven ventilators, a pulmonary diagnostic device and more than 100
respiratory accessories.

"This acquisition is an excellent strategic fit that brings together two leading
respiratory companies. The addition of the Infrasonics infant and high frequency
ventilator

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NELLCOR PURITAN BENNETT TO ACQUIRE INFRASONICS IN $66 MILLION TRANSACTION
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products fills a gap in a key area of the Nellcor Puritan Bennett product line,"
said C. Raymond Larkin, Jr., Nellcor Puritan Bennett's president and chief
executive officer. "The acquisition of Infrasonics continues to build on our
strategy of providing products to monitor, diagnose and treat the
respiratory-impaired patient. The combination of a broader product offering and
our comprehensive distribution channels will help us better serve the needs of
our customers worldwide."

"We believe this acquisition will enable us to recognize synergies through
revenue and earnings growth, new product development and sales and marketing
expansion," Mr. Larkin added. "We expect the acquisition to be accretive to
earnings in the first year, excluding the effect of transaction-related expenses
and other one-time charges."

Nellcor Puritan Bennett also announced that its board of directors approved a
2-for-1 split of the company's common stock, to take effect following approval
by its stockholders of an increase in the authorized number of shares of Nellcor
Puritan Bennett common stock. The stockholders will be asked to approve the
Infrasonics acquisition and the authorized share increase at a special meeting
of shareholders. Following the split and the acquisition of Infrasonics, Nellcor
Puritan Bennett will have approximately 60 million shares outstanding.

Finally, Nellcor Puritan Bennett announced that its board of directors has
approved certain amendments to the company's Rights Agreement to increase the
exercise price of the rights to $320 per right, to extend the term of the Rights
Agreement to March 8, 2006, and to make various other technical changes.

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NELLCOR PURITAN BENNETT TO ACQUIRE INFRASONICS IN $66 MILLION TRANSACTION
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This press release includes forward-looking statements which are subject to
change. The acquisition is subject to several conditions, including approval by
the stockholders of both companies and requisite regulatory approvals.
Additional information on factors that may affect the companies' businesses may
be found in their respective annual reports on Form 10-K together with their
recent respective quarterly reports on Form 10-Q.

Nellcor Puritan Bennett Incorporated is the worldwide leader in monitoring,
diagnosing, and treating the respiratory-impaired patient.

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