The KNIFE (Part 4091900100) is a genuine JACK original replacement part designed for JACK JK-T373, JK-T1377, Speedway SW 373D and SW 1377 Juki MB-373 Movable Knife series button sewing machines. Manufactured to OEM specifications for precise fit and reliable performance.
Equivalent Part Numbers
JACK: 4091900100
JUKI: B2406-373-000
Compatible Machines
This part fits the following industrial sewing machine models:
Looking for a replacement knife for your JACK JK-T373 or JK-T1377 button sewing machine? This genuine OEM part ensures reliable performance and precise fit. Shop with confidence — all parts ship from Miami, FL.
⚠️ Compatibility Notice: Always verify your machine model and subclass number before ordering. Part numbers and compatibility are provided as a reference only. Supra Sewing is not responsible for purchases made without confirming compatibility with your specific machine. All sales on replacement parts are final.
