Model # 34-350XL

Internet # 203999039

3/4 in. Lead-Free Double Check Valve Assembly

$121.77 /each

Frequently Bought Together

Product Overview

The Zurn Wilkins Model 350XL Backflow Preventer features a patented removable pressure vessel, facilitating check access for easy cleaning and repair. The valve is designed for installation on potable water lines to protect against both back-siphonage and backpressure of polluted water into the potable water supply. This backflow preventer is suitable for use in residential, commercial, industrial, and irrigation applications where a health hazard does not exist.

  • Removable pressure vessel is serviceable offline and reusable, resulting in reduced labor costs, the ease of repair and replacement significantly decreases water system downtime by 300 percent, a benefit for both service professional and end user
  • Made of UV resistant composite material, the pressure vessel exceeds bronze performance levels, including severe water conditions, the composite material also acts as a theft deterrent, with less bronze material used in the overall production
  • Top access to test cocks and shutoff valves and check assembly makes the unit easy to test
  • Easy to winterize by removing pressure vessel between shutoff valves
  • Short lay length
  • ASSE listed 1015, IAPMO listed, CSA certified B64.5, AWWA compliant C510, approved by the Foundation for Cross Connection Control and Hydraulic Research at the University of Southern California, NSF listed - Standard 61, annex G

Info & Guides

You will need Adobe® Acrobat® Reader to view PDF documents.  Download a free copy from the Adobe Web site.



Inlet size (in.) 
Product Depth (in.) 
Product Height (in.) 
Product Length (in.) 
Product Width (in.) 


Above ground 
Irrigation System Component 
Irrigation Valve Type 
Backflow prevention 
Pressure Rating 
Valve Type 
Double Check 

Warranty / Certifications

Manufacturer Warranty 
All goods sold hereunder are warranted to be free from defects in material and factory workmanship for a period on one year from date of purchase. 

More Products With These Features


Customer Questions & Answers

2 Questions1 Answer

Customer Questions & Answers

3/4 in. Lead-Free Double Check Valve Assembly
3/4 in. Lead-Free Double Check Valve Assembly

Ask your questions. Share your answers.

Clear Search Term
Sort By:
1 answer

will this valve input fertizer into system

This question is from 3/4 in. Lead-Free Double Check Valve Assembly
Asked by
Boyd, Texas
Read all my Q&A
May 18, 2016
0out of 0found this question helpful.
Was this helpful?helpful0unhelpful0

Answer (1)

May 19, 2016
This will work for that purpose.
1out of 1found this answer helpful.
Was this helpful?helpful1unhelpful0
0 answers

how do I turn on backflow device?

This question is from 3/4 in. Lead-Free Double Check Valve Assembly
Asked by
Read all my Q&A
June 6, 2015
The Wilkins 350 is a double check valve assembly ( DCA ). It is available in ¾” – 2” sizes and has been in production since 2004. The body is made of reinforced nylon with a bronze carriage. A lead free version was introduced in 2010 (350XL).

the only valve that looks closed is the one next to the house. This unit is in a box in the ground
0out of 0found this question helpful.
Was this helpful?helpful0unhelpful0
1 of 1
  • 2016-07-29 T15:05:22.309-05:00
  • bvseo_lps, prod_bvqa, vn_prr_5.6
  • cp-1, bvpage1
  • co_hasquestionsanswers
  • loc_en_US, sid_203999039, prod, sort_default
1 of 1
  • bvseo_sdk, java_sdk, bvseo-3.1.1
  • CLOUD, getContent, 139ms

Customer Reviews

Rated 4.5 out of 5 by 2 reviewers.
Rated 5.0 out of 5.0 by Replacement for failed double check valve in home irrigation system Had to get a new double check valve on my yard's irrigation system to comply with rules requiring annual inspections to make sure there is no irrigation system backflow into my community water system. The old valve had failed after 16 years. My inspector highly recommended this model. I got one quote for the Wilkins 350 XL from my plumber who quoted my $270. I found it for $115 at Home Depot. I told my plumber and he said buy it at that price because his cost was higher than that. He was still happy to have the installation work. Just passed inspection...so far, so good. March 8, 2016
Rated 4.0 out of 5.0 by great value Easy to install seams durable at A reasonable price March 31, 2015
  • 2016-07-29 T15:27:52.787-05:00
  • bvseo_lps, prod_bvrr, vn_prr_5.6
  • cp-1, bvpage1
  • co_hasreviews, tv_2, tr_2
  • loc_en_US, sid_203999039, prod, sort_default
1-2 of 2
  • bvseo_sdk, java_sdk, bvseo-3.1.1
  • CLOUD, getContent, 108ms