Description
Additional Details
Purchase History
General Ledger Coding

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The 4" x 50' Aluminum Flexible Duct is a UL 181 Class 1 certified air connector designed for low to medium pressure HVAC systems. Constructed from a durable multi-ply laminate of metalized polyester and aluminum, it features a 1-inch pitch steel wire helix for superior structural integrity and flexibility. This duct is ideal for bathroom fan exhaust and general ventilation applications, offering a reliable temperature range of -20°F to 180°F. Its encapsulated wire design ensures the helix does not unravel when cut to length, providing a clean and efficient installation for professional builders.

UL® 181 class 1 certified marked and listed duct. Do not install in lengths greater than 14 feet. Temperature range: -20°F to + 180°F. Ideal for bath fan exhaust ventilation applications. Constructed with multiple layers of aluminum/polyester material. Steel wire support. Flexible design for easier installation. Do not use for dryer venting, cooking appliances or heating unless approved and recommended by the appliance manufacturer. Size - 4” x 50’

Packaging/Shipping Size and Weight: Length: 18.75" | Width: 10.75" | Height: 5.25" | Weight: 4 lbs

Features

UL 181, Class 1 air connector label
Multi-ply design of metabolized polyester and aluminum/polyester laminate
Steel wire support
3 in diameter has 3/4 in pitch
4-12 in diameter has 1 in pitch
UL sticker every 10 ft

Product Details
brand:	Builder's Best
type:	Flexible Duct
material:	Aluminum/Polyester
size:	4" x 50'
ul_listing:	UL181 Class 1
Color:	Silver
Finish:	Metallic
Material:	Aluminum/Polyester
Size:	4" x 50'
Certification:	UL 181 Class 1 Air Connector
Temperature Range:	-20°F to 180°F
Wire Support:	1-inch pitch steel wire helix
Application:	Bathroom fan exhaust and general venting
Installation Note:	Do not install in lengths greater than 14 feet per UL 181 Class 1 requirements
Length:	50
Series:	181
Special Features:	1 in Pitch
Standards:	NFPA Certified
Type:	Flexible
Usage:	For Low to Medium Operating Pressures in HVAC Systems

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General Ledger Coding

General Ledger Coding is a value added service provided for you at no additional cost.

General Ledger Coding makes accounting easier by providing you with a calculated total of purchases based on your General Ledger Codes.

In addition to traditional General Ledger Summary provided at time of invoice, we can also provide quotes and order acknowledgements with General Ledger Coding as well. We also give you the ability to change a GL Code for one or all items for renovation projects that may utilize a single GL Code. We can also code any of our "extended inventory" items with your General Ledger Code at the time of quote, order confirmation and invoicing as well. We can code our item numbers directly to your GL Codes should our item categories not align directly with your GL Code Categories.

Please contact us if you wish to implement our General Ledger Coding feature.