SMC Check Valves for Air or Liquid
Product Video
Product Video

SMC Check Valves for Air or Liquid

The 694, 693, 685, and 687 Series check valves can be used for a wide range of air and fluid applications.

  • Polypropylene
  • EPDM, Buna, Aflas®, or FKM seals
  • Hastelloy or 302 stainless steel spring
  • High flow rate
  • Seat area open diameter: 0.438"
  • Positive seal at very low back pressure or slight vacuum
  • Maximum pressure: 125 psi
  • Maximum temperature: 140°F
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Stock Description Catalog Pg. Price
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22231
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.62/Each
In Stock
Save 5%12+$7.24/Each
Save 10%24+$6.86/Each
Save 15%72+$6.48/Each
 P-447
$7.62/Each
In Stock
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22637
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.28/Each
Out of Stock (On Order)
Save 5%12+$6.92/Each
Save 10%24+$6.55/Each
Save 15%72+$6.19/Each
 P-447
$7.28/Each
Out of Stock (On Order)
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22638
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.28/Each
Out of Stock (On Order)
Save 5%12+$6.92/Each
Save 10%24+$6.55/Each
Save 15%72+$6.19/Each
 P-447
$7.28/Each
Out of Stock (On Order)
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
22639
1/4" FNPT x 1/4" FNPT Series 694 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
$10.44/Each
Out of Stock (On Order)
Save 5%12+$9.92/Each
Save 10%24+$9.40/Each
Save 15%72+$8.87/Each
 P-447
$10.44/Each
Out of Stock (On Order)
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22232
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.84/Each
In Stock
Save 5%12+$7.45/Each
Save 10%24+$7.06/Each
Save 15%72+$6.66/Each
 P-447
$7.84/Each
In Stock
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22640
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.48/Each
In Stock
Save 5%12+$7.11/Each
Save 10%24+$6.73/Each
Save 15%72+$6.36/Each
 P-447
$7.48/Each
In Stock
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22641
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.48/Each
In Stock
Save 5%12+$7.11/Each
Save 10%24+$6.73/Each
Save 15%72+$6.36/Each
 P-447
$7.48/Each
In Stock
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with FKM Seals, 1/3 Cracking Pressure & Hastelloy Spring
22642
3/8" FNPT x 3/8" FNPT Series 693 Polypropylene Check Valve with FKM Seals, 1/3 Cracking Pressure & Hastelloy Spring
$10.65/Each
In Stock
Save 5%12+$10.12/Each
Save 10%24+$9.59/Each
Save 15%72+$9.05/Each
 P-447
$10.65/Each
In Stock
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22210
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$8.36/Each
In Stock
Save 5%12+$7.94/Each
Save 10%24+$7.52/Each
Save 15%72+$7.11/Each
 P-447
$8.36/Each
In Stock
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22643
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.95/Each
Out of Stock (On Order)
Save 5%12+$7.55/Each
Save 10%24+$7.16/Each
Save 15%72+$6.76/Each
 P-447
$7.95/Each
Out of Stock (On Order)
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22644
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$7.95/Each
In Stock
Save 5%12+$7.55/Each
Save 10%24+$7.16/Each
Save 15%72+$6.76/Each
 P-447
$7.95/Each
In Stock
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals/No Spring
22645
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals/No Spring
$7.95/Each
Out of Stock (On Order)
Save 5%12+$7.55/Each
Save 10%24+$7.16/Each
Save 15%72+$6.76/Each
 P-447
$7.95/Each
Out of Stock (On Order)
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
22352
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
$11.31/Each
In Stock
Save 5%12+$10.74/Each
Save 10%24+$10.18/Each
Save 15%72+$9.61/Each
 P-447
$11.31/Each
In Stock
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with FKM Seals, 3 PSI Cracking Pressure & Hastelloy Spring
22646
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with FKM Seals, 3 PSI Cracking Pressure & Hastelloy Spring
$11.78/Each
Out of Stock (On Order)
Save 5%12+$11.19/Each
Save 10%24+$10.60/Each
Save 15%72+$10.01/Each
 P-447
$11.78/Each
Out of Stock (On Order)
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals, 7 PSI Cracking Pressure & Hastelloy Spring
22647
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals, 7 PSI Cracking Pressure & Hastelloy Spring
$11.84/Each
Out of Stock (On Order)
Save 5%12+$11.25/Each
Save 10%24+$10.66/Each
Save 15%72+$10.06/Each
 P-447
$11.84/Each
Out of Stock (On Order)
1/2" FNPT x 1/2" MNPT Series 685 Polypropylene Check Valve with EPDM Seals, 7 PSI Cracking Pressure & Hastelloy Spring
22648
1/2" FNPT x 1/2" MNPT Series 685 Polypropylene Check Valve with EPDM Seals, 7 PSI Cracking Pressure & Hastelloy Spring
$11.84/Each
In Stock
Save 5%12+$11.25/Each
Save 10%24+$10.66/Each
Save 15%72+$10.06/Each
 P-447
$11.84/Each
In Stock
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with Aflas® Seals, 3 PSI Cracking Pressure & Hastelloy Spring
22649
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with Aflas® Seals, 3 PSI Cracking Pressure & Hastelloy Spring
$17.06/Each
In Stock
Save 5%12+$16.21/Each
Save 10%24+$15.35/Each
Save 15%72+$14.50/Each
 P-447
$17.06/Each
In Stock
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
22650
1/2" FNPT x 1/2" FNPT Series 685 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
$11.30/Each
In Stock
Save 5%12+$10.74/Each
Save 10%24+$10.17/Each
Save 15%72+$9.61/Each
 P-447
$11.30/Each
In Stock
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22211
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$9.45/Each
In Stock
Save 5%12+$8.98/Each
Save 10%24+$8.51/Each
Save 15%72+$8.03/Each
 P-447
$9.45/Each
In Stock
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22651
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$9.00/Each
In Stock
Save 5%12+$8.55/Each
Save 10%24+$8.10/Each
Save 15%72+$7.65/Each
 P-447
$9.00/Each
In Stock
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22652
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$9.99/Each
Special Order
Save 5%12+$9.49/Each
Save 10%24+$8.99/Each
Save 15%72+$8.49/Each
 P-447
$9.99/Each
Special Order
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
22653
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
$11.84/Each
Out of Stock (On Order)
Save 5%12+$11.25/Each
Save 10%24+$10.66/Each
Save 15%72+$10.06/Each
 P-447
$11.84/Each
Out of Stock (On Order)
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals/No Spring
22654
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals/No Spring
$9.00/Each
In Stock
Save 5%12+$8.55/Each
Save 10%24+$8.10/Each
Save 15%72+$7.65/Each
 P-447
$9.00/Each
In Stock
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals, 1/2 PSI Cracking Pressure & 302 SS Spring
22655
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with Buna-N Seals, 1/2 PSI Cracking Pressure & 302 SS Spring
$13.55/Each
In Stock
Save 5%12+$12.87/Each
Save 10%24+$12.20/Each
Save 15%72+$11.52/Each
 P-447
$13.55/Each
In Stock
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
22656
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with EPDM Seals, 1/3 PSI Cracking Pressure & 302 SS Spring
$9.00/Each
In Stock
Save 5%12+$8.55/Each
Save 10%24+$8.10/Each
Save 15%72+$7.65/Each
 P-447
$9.00/Each
In Stock
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
22657
3/4" FNPT x 3/4" FNPT Series 687 Polypropylene Check Valve with FKM Seals, 1/3 PSI Cracking Pressure & Hastelloy Spring
$12.28/Each
In Stock
Save 5%12+$11.67/Each
Save 10%24+$11.05/Each
Save 15%72+$10.44/Each
 P-447
$12.28/Each
In Stock

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