Bobbin Case for 20U Zig-Zag Sewing Machines #541678NBL Universal

Bobbin Case for 20U Zig-Zag Sewing Machines  #541678NBL Universal

L-Size Bobbin Case • NBL No-Back-Lash System • 21 mm Bobbin Diameter • Industrial Zig-Zag & Compatible Embroidery Machines

The Bobbin Case #541678NBL is an L-size No-Back-Lash (NBL) bobbin case designed for compatible SINGER® 20U series zig-zag sewing machines and other industrial sewing and embroidery machines that use L-size bobbins.

This bobbin case is equipped with an integrated brake spring that applies light, continuous pressure to the bobbin. This helps control bobbin momentum when the sewing machine starts and stops, allowing the bobbin to stop rotating faster and helping reduce excess thread unwinding, tangling, and inconsistent bobbin thread control.

Designed for bobbins with an approximate 21 mm diameter, the #541678NBL is a practical replacement for compatible industrial zig-zag machines as well as selected commercial embroidery machines using the same L-size bobbin system.

Key Features

• Part Number: 541678NBL.
• L-Size Bobbin Case: Designed for compatible machines using L-size bobbins.
• 21 mm Bobbin Diameter: Designed for compatible bobbins measuring approximately 21 mm in diameter.
• NBL — No-Back-Lash Design: Helps control unwanted bobbin rotation during rapid machine starts and stops.
• Integrated Brake Spring: Applies light pressure to the bobbin to help control momentum.
• Improved Thread Control: Helps reduce excessive bobbin thread unwinding and tangling.
• Zig-Zag Machine Compatibility: Designed for compatible SINGER® 20U series and comparable machines.
• Embroidery Machine Applications: Also fits selected commercial embroidery machines using compatible L-size bobbins.

Compatible Machines

The following is a partial compatibility list. Always verify your exact machine model and bobbin system before ordering.

• SINGER®: 20U, P20U33, P20U143
• Alphasew: P20U33-3
• Artisan: 20-3, 20-53, 20U-143
• Barudan: BEAM, BEL, BELL, BEM
• Brother®: B651, B652, TZ1, XL622, XL702, XL703, XL2005, XL4001, XL5001
• Happy: HCM, HM4, HMF, HMS, J-4, J-7, J-8, K-4, K-7, K-8
• Meistergram: M100, M600, M700

Technical Specifications

How the NBL System Works

During rapid sewing, the bobbin can continue spinning momentarily after the machine stops because of rotational momentum. The No-Back-Lash brake spring applies controlled pressure to the bobbin, helping it stop more quickly. This reduces unnecessary thread unwinding inside the bobbin case and helps prevent loose thread and tangling during repeated start-and-stop sewing operations.

The Bobbin Case #541678NBL provides an L-size No-Back-Lash solution for compatible Universal 20U zig-zag machines and selected industrial and embroidery machines, helping improve bobbin control and reduce unwanted thread unwinding during start-and-stop sewing operations.