Needle Bar Thread Guide. This essential component ensures the thread stays perfectly aligned as it enters the needle, preventing fraying, snapping, and skipped stitches at high speeds.

This part is the direct successor to older models and is compatible with both part numbers: 410904 and 540663.

Compatible Singer Models:
This needle bar thread guide is a precision fit for the following Singer Industrial models:

Singer 491D

Singer 591

Singer 601D

Key Features:
Dual Part Number Compatibility: Seamlessly replaces original part numbers 410904 and 540663.

Ultra-Smooth Finish: Polished surfaces reduce friction and heat buildup, protecting your thread from damage during high-speed operation.

Perfect Alignment: Engineered to maintain the exact angle required for consistent loop formation and stitch precision.

Durable Steel Construction: Built to resist the constant wear of industrial thread movement, ensuring a long service life.

Orders are typically processed within 1–3 business days.

We ship from our Georgia, USA warehouse. If an item is temporarily unavailable in the U.S., we source it through our global supplier network and will notify you of the estimated lead time.

Free shipping is available on U.S. orders over $99.

Once your order ships, you will receive a tracking number by email.

For urgent orders or shipping questions, please contact us before placing your order.

We stand behind the quality of the products we sell.

• Genuine OEM parts are covered by the manufacturer's warranty where applicable.

• Aftermarket and generic parts are covered against manufacturing defects.

• If you receive a damaged, defective, or incorrect item, please contact us within 30 days of delivery.

• Warranty does not cover damage caused by improper installation, misuse, normal wear, or modifications.

If you have any questions, our support team is happy to help before or after your purchase.