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ZURN Double Check Backflow Preventer: 350AST, 4 in Pipe Size, Flange x Flange - Zurn Double Check Backflow Preventers
ZURNZurn Double Check Backflow Preventers

ZURN Double Check Backflow Preventer: 350AST, 4 in Pipe Size, Flange x Flange

The ZURN 350AST is a 4-inch double check backflow preventer with flange x flange connections and NRS gate valve shut-off valves. This model, MPN 4-350AST, has an overall length of 34.88 inches.

SKU 3G-OTH-439830

Also listed as: 4350AST · 4 350AST

Brand
ZURN
Item
Double Check Backflow Preventer: 350AST, 4 in Pipe Size, Flange x Flange
Category
Zurn Double Check Backflow Preventers
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

ZURN
Manufacturer Part Number
4-350AST
Type
Flange x Flange
Overall Lg
34.88 in
Pipe Size
4 in
Connection Type
Flange x Flange
Shut-Off Valve Type
NRS Gate Valve

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ZURN Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The ZURN 350AST is a 4-inch double check backflow preventer with flange x flange connections and NRS gate valve shut-off valves. This model, MPN 4-350AST, has an overall length of 34.88 inches.

Frequently Asked Questions

What is the ZURN 350AST double check backflow preventer used for?

The ZURN 350AST double check backflow preventer is used in commercial and industrial water systems to prevent reverse flow of contaminated water into the potable supply. It is commonly installed in fire sprinkler systems, irrigation lines, and process water applications where non-health-hazard cross-connections exist.

What are the specifications of the ZURN 4-350AST backflow preventer?

The ZURN 4-350AST is a 4-inch double check backflow preventer with flange x flange connections and NRS gate valve shut-off valves. Its overall length is 34.88 inches. The manufacturer part number is 4-350AST. It is designed for non-health-hazard applications and meets industry standards for backflow prevention.

Where to buy the ZURN 4-350AST backflow preventer worldwide?

3G Electric supplies the ZURN 4-350AST double check backflow preventer worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time. We source and deliver this ZURN model to any country.

How to install a ZURN double check backflow preventer?

Install the ZURN double check backflow preventer in a horizontal or vertical position with flow arrow pointing downstream. Ensure flange connections are properly gasketed and bolted to matching pipe flanges. Provide adequate clearance for maintenance and testing. Always follow local plumbing codes and the manufacturer's installation manual for proper operation.

Used in

Common applications for ZURN
Commercial restrooms — ZURN AquaVantage® automatic flush valves (ZER6000AV series) for water-efficient toilet flushing
Institutional kitchens — ZURN cast iron floor drains (ZN415 series) for heavy-duty drainage in food preparation areas
Industrial washdown areas — ZURN height-adjustable PVC floor drains (EZ1 series) for chemical-resistant drainage
Hospital patient rooms — ZURN dome strainers (P1910 series) for floor sink drainage in sanitary environments
Office building maintenance — ZURN chrome-plated brass P-traps (ZR365B-PC) for sink trap replacements
Urinal retrofit projects — ZURN ZTR sensor flush valve retrofit kits (ZTR6203 series) for upgrading manual urinal flush valves

ZURN Products

3G Electric supplies ZURN zurn double check backflow preventers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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