Overlock knife/blade compatible across the modern overlock family (JACK E4S/E5/C-series, Speedway SW6/SW7, and equivalents). Knives cross thread counts within the family.
The Lower Looper (Part 20717006) is a genuine JACK original replacement part designed for JACK E4S-3 and E4S-5 series overlock machines. Manufactured to OEM specifications for precise fit and reliable performance.
Equivalent Part Numbers
JACK: 20717006
Compatible Machines
This part fits the following industrial sewing machine models:
Looking for a replacement lower looper for your JACK E4S-3 or E4S-5 overlock 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.
