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Polyester Filament Thread – Size 346 Tex 350

Polyester Filament Thread – Size 346 Tex 350 is an ultra-heavy-duty sewing thread made from strong and durable polyester filaments. It is known for its extremely high tensile strength, excellent color fastness, and resistance to abrasion.

Size 346 Tex 350 Polyester Filament Thread
Size 346 Tex 350 Polyester Filament Thread

Recommended Needle Size

The recommended needle size range is from 220/26 to 260/28. Using a needle within this range will ensure the best match between the thread and the fabric, resulting in optimal sewing performance.


Polyester Filament Thread – Size 346 Tex 350 is ideal for use in extremely heavy-duty applications, including sewing upholstery, tarps, and canvas materials for outdoor applications. It is often used in the production of industrial bags, tarpaulins, and safety harnesses.


Polyester Filament Thread – Size 346 Tex 350 has many benefits. First, its incredibly strong and durable fibers make it ideal for the most demanding projects that require long-lasting results. Second, its excellent color fastness ensures that the thread will retain its color even after repeated washing and exposure to sunlight. Finally, its resistance to abrasion makes it suitable for use in harsh environments.

Learn More: Polyester Thread/Bonded Polyester Thread

Exceptional Strength

Size 346 Tex 350 polyester filament thread is known for its outstanding strength. It has a high tensile strength, which allows it to withstand heavy loads and tension. This makes it suitable for sewing applications that require robust and durable stitching.

Heavy-Duty Applications

The strength of size 346 Tex 350 polyester filament thread makes it ideal for heavy-duty sewing tasks. It can handle demanding projects such as automotive upholstery, leatherwork, canvas stitching, and other applications that require stitching thick or dense materials.

Abrasion Resistance

Polyester filament thread is resistant to abrasion, meaning it can withstand friction and rubbing without breaking or wearing down easily. This quality is valuable in applications where the thread is exposed to rough surfaces or constant use, ensuring the longevity and durability of the stitches.

Chemical Resistance

Polyester filament thread offers good chemical resistance, making it suitable for applications where exposure to chemicals or cleaning agents is likely. It can resist mild acids, alkaline substances, and common household cleaning products without deteriorating or weakening.

UV Resistance

Polyester filament thread is resistant to ultraviolet (UV) rays, allowing it to be used in outdoor applications without significant degradation or fading when exposed to sunlight. This makes it suitable for outdoor gear, awnings, marine applications, and other products that require UV resistance.

Low Stretch

Size 346 Tex 350 polyester filament thread has minimal stretch, ensuring that the stitches remain tight and secure. This is particularly important in applications where maintaining tension and preventing seam slippage is crucial, such as in upholstery, heavy fabrics, or projects that require long-lasting seams.


Polyester filament thread offers excellent colorfastness, meaning it retains its color even after exposure to sunlight, washing, or chemical treatments. This quality ensures consistent thread color and longevity in projects that require color retention, such as quilting, embroidery, or decorative stitching.

Easy Care

Polyester filament thread is easy to care for and maintain. It is machine washable, can withstand high temperatures during ironing, and is resistant to shrinkage. This makes it convenient for use in a wide range of projects that require regular washing or exposure to heat.


The following table outlines the main properties of Polyester Filament Thread – Size 346 Tex 350:

Thread TypePolyester Filament Thread
Tex Size350
Average StrengthPounds: 62.0
Kilograms: 28.1
Average ThicknessInches: 0.0226
Millimeters: 0.5740
Recommended Needle Size220/26 to 260/28

These properties make Polyester Filament Thread – Size 346 Tex 350 the ultimate choice for the most demanding heavy-duty sewing projects. It produces even and precise stitching, has extremely high strength, and can withstand severe wear and tear, making it a reliable and durable choice for professional and hobbyist sewers.