Exhibit 99.1

Pentair, Inc.

5500 Wayzata Blvd., Suite 800

Golden Valley, MN 55416

763 545 1730 Tel

763 656 5204 Fax

News Release [LOGO OF PENTAIR]

Pentair’s First Quarter 2004 EPS Rises 43% to $0.80 on 20% Sales Gain

GOLDEN VALLEY, Minn. — April 26, 2004 — Pentair (NYSE: PNR) announced that its first quarter 2004 earnings per share (EPS) of $0.80 increased 43 percent over EPS of $0.56 in the same period last year. Pentair’s first quarter 2004 net sales totaled $767.1 million, up 20 percent from $637.5 million in the same period a year ago. Removing the effects of an acquisition, favorable currency translation, and four additional days in the first quarter 2004, sales were up approximately 11 percent over the first quarter 2003. Operating income for the first quarter 2004 totaled $73.0 million, 40 percent greater than the $52.2 million reported in the first quarter of 2003. First quarter 2004 free cash flow of negative $4 million was a $6 million improvement compared to the same period last year. Pentair expects to generate free cash flow in excess of $200 million in 2004.

“The value of our strategic initiatives and efforts to drive growth paid off well in the first quarter, with our water, enclosures, and tools businesses all delivering strong organic growth,” said Pentair chairman and chief executive officer, Randall J. Hogan. “The strength of our first quarter performance demonstrates our ability to translate substantial sales gains into exceptional income improvements.”

In the Water Technologies Group, first quarter 2004 sales of $314.0 million were 27 percent higher than the $246.4 million recorded in the same period last year. Growth across all of the water businesses, both domestic and international, contributed to the Group’s improved performance. On an organic basis, after excluding sales from the Everpure acquisition, favorable currency translation, and the extra days in the quarter, the Group’s first quarter growth rate was about 13 percent.

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First quarter 2004 operating income totaled $41.5 million in Water Technologies, a 41 percent gain over the same period last year. Higher volumes, on-going productivity improvements driven by the Pentair Integrated Management System (PIMS), and supply management savings contributed to the excellent performance. All businesses contributed to a 120 basis point margin improvement, which boosted first quarter margins from 12.0 percent to 13.2 percent. The newly acquired Everpure commercial filtration business was accretive to earnings in the first quarter of Pentair’s ownership.

Pentair’s Enclosures Group delivered 25 percent sales growth with first quarter 2004 sales totaling $174.8 million compared to a year-earlier total of $139.5 million. Excluding favorable currency translation and after adjusting for the extra days in the quarter, the Group’s first quarter sales improved about 15 percent over the same period last year. Strong industrial demand and a rebound in telecom markets combined with the results of growth initiatives targeting medical, security, defense, and food & beverage markets to drive increased sales activity in the quarter.

First quarter operating income in the Enclosures Group increased 96 percent from the same period last year, totaling $19.4 million in 2004 versus $9.9 million in 2003. Margins improved 400 basis points to 11.1 percent on the same comparison. The first quarter of 2004 marked the ninth consecutive quarter of sequential margin improvement for the Enclosures Group. The increased margins benefited from higher volume and productivity resulting from the successful implementation of PIMS and supply management initiatives.

In the Tools Group, the first quarter marked the second consecutive quarter of year-over-year sales gains and set a new all-time record for first quarter sales. Sales increased some 11 percent to $278.7 million versus $251.8 million in the same period last year, largely because of demand for pneumatic and other portable power tools and pressure washers. Excluding favorable currency translation and after adjusting for the extra days in the quarter, the Group’s first quarter sales improved about seven percent over the same period last year.

Operating income for the Tools Group totaled $20.8 million, a 17 percent gain over the same period last year driven by higher sales volume and cost savings generated by the Group’s PIMS and supply management programs. Margins gained 50 basis points in the first quarter versus both the first quarter of 2003 and the fourth quarter of 2003.

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In early April 2004, Pentair completed the purchase of its Asian Tools joint venture business. Pentair had acquired an initial 40 percent ownership stake in the joint venture in 2001 and subsequently increased its ownership to 49 percent in 2003.

Pentair noted that the Federal Trade Commission is reviewing the proposed acquisition of WICOR Industries. Pentair expects to complete the WICOR transaction in the second or third quarter of this year. Similarly, Pentair’s review of strategic alternatives for its Tools Group continues on-schedule.

“All of our businesses did a great job of managing the materials cost increases that we experienced during the first quarter, and several of our units set new performance records,” Hogan said. “These strong results lend confidence to our expectations for the second quarter and full year 2004. Based on current economic conditions and our successful growth activities, we expect organic sales growth in the mid- to high-single digits for the remainder of the year. Before any impact from WICOR, we now anticipate second quarter EPS of between $1.00 and $1.05 and full year EPS of between $3.45 and $3.60.”

A Pentair conference call scheduled for 11:00 a.m. CDT today will be webcast live via http://www.pentair.com. A link to the conference call is posted on the site’s “Financial Information” page and will be archived at the same location.

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Pentair, Inc. and Subsidiaries

Condensed Consolidated Statements of Income (Unaudited)

	Three months ended
In thousands, except per-share data	April 3 2004			March 29 2003
Net sales	$	767,141		$	637,516
Cost of goods sold		565,483			482,225
Gross profit		201,658			155,291
% of net sales		26.3	%		24.4	%
Selling, general and administrative		116,695			92,982
% of net sales		15.2	%		14.6	%
Research and development		11,927			10,121
% of net sales		1.6	%		1.6	%
Operating income		73,036			52,188
% of net sales		9.5	%		8.2	%
Net interest expense		11,174			9,993
% of net sales		1.5	%		1.6	%
Income before income taxes		61,862			42,195
% of net sales		8.1	%		6.6	%
Provision for income taxes		21,652			14,346
Effective tax rate		35.0	%		34.0	%
Net income	$	40,210		$	27,849
Earnings per common share
Basic	$	0.82		$	0.56
Diluted	$	0.80		$	0.56
Weighted average common shares outstanding
Basic		49,214			49,348
Diluted		50,265			49,617
Cash dividends declared per common share	$	0.21		$	0.19

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Pentair, Inc. and Subsidiaries

Condensed Consolidated Statements of Income (Unaudited)

In thousands	April 3 2004			December 31 2003			March 29 2003
Assets
Current assets
Cash and cash equivalents	$	63,247		$	47,989		$	44,604
Accounts and notes receivable, net		496,548			420,403			438,642
Inventories		309,728			285,577			309,969
Deferred tax assets		49,746			50,989			55,157
Prepaid expenses and other current assets		30,952			24,493			21,303
Total current assets		950,221			829,451			869,675
Property, plant and equipment, net		332,926			343,550			344,734
Other assets
Goodwill		1,373,575			1,373,549			1,233,918
Intangibles, net		107,003			108,118			19,042
Other		125,472			126,009			110,818
Total other assets		1,606,050			1,607,676			1,363,778
Total assets	$	2,889,197		$	2,780,677		$	2,578,187
Liabilities and Shareholders’ Equity
Current liabilities
Current maturities of long-term debt	$	4,884		$	73,631		$	58,038
Accounts payable		213,164			170,077			182,360
Employee compensation and benefits		74,177			84,587			66,190
Accrued product claims and warranties		39,480			37,148			38,195
Income taxes		28,989			13,198			23,757
Other current liabilities		116,126			118,810			104,721
Total current liabilities		476,820			497,451			473,261
Long-term debt		829,135			732,862			719,770
Pension and other retirement compensation		101,250			101,704			126,073
Post-retirement medical and other benefits		41,922			42,134			42,417
Deferred tax liabilities		78,580			78,532			32,741
Other noncurrent liabilities		61,541			66,516			57,943
Total liabilities		1,589,248			1,519,199			1,452,205
Shareholders’ equity		1,299,949			1,261,478			1,125,982
Total liabilities and shareholders’ equity	$	2,889,197		$	2,780,677		$	2,578,187
Days sales in accounts receivable (13 month moving average)		55			56			59
Days inventory on hand (13 month moving average)		61			63			63
Days in accounts payable (13 month moving average)		51			51			53
Debt/total capital		39.1	%		39.0	%		40.9	%

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Pentair, Inc. and Subsidiaries

Condensed Consolidated Statements of Cash Flows (Unaudited)

	Three months ended
In thousands	April 3 2004			March 29 2003
Operating activities
Net income	$	40,210		$	27,849
Depreciation		15,557			15,609
Other amortization		3,258			1,281
Deferred income taxes		1,606			1,056
Stock compensation		—			208
Changes in assets and liabilities, net of effects of business acquisitions and dispositions
Accounts and notes receivable		(76,607	)		(33,032	)
Inventories		(25,742	)		(13,436	)
Prepaid expenses and other current assets		(18,298	)		(2,009	)
Accounts payable		43,408			9,747
Employee compensation and benefits		(11,086	)		(18,066	)
Accrued product claims and warranties		2,380			647
Income taxes		15,874			11,381
Other current liabilities		11,818			(6,284	)
Pension and post-retirement benefits		98			580
Other assets and liabilities		780			2,186
Net cash provided by (used for) continuing operations		3,256			(2,283	)
Net cash used for discontinued operations		(331	)		(118	)
Net cash provided by (used for) operating activities		2,925			(2,401	)
Investing activities
Capital expenditures		(6,955	)		(7,711	)
Payments from sale of businesses		—			(2,400	)
Acquisitions, net of cash acquired		(2,296	)		(14,579	)
Equity investments		—			142
Net cash used for investing activities		(9,251	)		(24,548	)
Financing activities
Net short-term repayments		—			(705	)
Proceeds from long-term debt		85,816			204,558
Repayment of long-term debt		(62,485	)		(160,642	)
Proceeds from exercise of stock options		9,344			59
Dividends paid		(10,457	)		(9,376	)
Net cash provided by financing activities		22,218			33,894
Effect of exchange rate changes on cash		(634	)		(1,989	)
Change in cash and cash equivalents		15,258			4,956
Cash and cash equivalents, beginning of period		47,989			39,648
Cash and cash equivalents, end of period	$	63,247		$	44,604
Free cash flow
Net cash provided by operating activities	$	2,925		$	(2,401	)
Less capital expenditures		(6,955	)		(7,711	)
Free cash flow	$	(4,030	)	$	(10,112	)

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Pentair, Inc. and Subsidiaries

Supplemental Financial Information by Reportable Business Segment (Unaudited)

In thousands	First Qtr 2004			First Qtr 2003
Net sales to external customers
Water	$	314,002		$	246,440
Enclosures		174,803			139,453
Tools		278,688			251,765
Intersegment sales elimination		(352	)		(142	)
Consolidated	$	767,141		$	637,516
Operating income (loss)
Water	$	41,547		$	29,504
Enclosures		19,354			9,865
Tools		20,763			17,686
Other		(8,628	)		(4,867	)
Consolidated	$	73,036		$	52,188
Operating income as a percent of net sales
Water		13.2	%		12.0	%
Enclosures		11.1	%		7.1	%
Tools		7.5	%		7.0	%
Consolidated		9.5	%		8.2	%

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About Pentair, Inc.

Pentair (www.pentair.com) is a diversified operating company headquartered in Minnesota. Its Water Technologies Group is a global leader in providing innovative products and systems used worldwide in the movement, treatment, storage and enjoyment of water. Pentair’s Enclosures group is a leader in the global enclosures market, serving industrial and electronic customers, and its Tools Group markets innovative products under established brand names to professionals and do-it-yourself users. Pentair’s 2003 revenues totaled $2.7 billion. The company employs 12,500 people in more than 50 locations around the world.

Any statements made about the company’s anticipated financial results are forward-looking statements subject to risks and uncertainties such as continued economic growth; foreign currency effects; retail and industrial demand; product introductions; and pricing and other competitive pressures. Forward-looking statements included herein are made as of the date hereof and the company undertakes no obligation to update publicly such statements to reflect subsequent events or circumstances. Actual results could differ materially from anticipated results.

Contact

Pentair:        Mark Cain

Tel.:              (763) 656-5278

E-mail:         mark.cain@pentair.com

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