KST 140XB Weed Eater Head Replacement Compatible with Kobalt 80V 140XB 2908003 1315033 1315053 2908503 623439 670250 Straight Brushless Cordless String Trimmer,Replacement Head for Kobalt

What It Is

The KST 140XB is a replacement trimmer head designed for Kobalt 80V straight shaft brushless cordless string trimmers. It holds standard .080" or .095" trimmer line and uses a bump-feed mechanism to advance line as you work.

Fitment & Compatibility

Check your model number first. This head fits Kobalt 80V models: 140XB, 2908003, 1315033, 1315053, 2908503, 623439, and 670250. It will not fit curved shaft trimmers or older Kobalt 40V models.

Measure your shaft diameter. This head requires a 0.5" (12.7mm) shaft. If your trimmer shaft is larger or smaller, it won’t mount.

Confirm the drive hole pattern. The head uses a standard 3-hole pattern with a 0.25" center hole. If your trimmer uses a different drive system (e.g., square or star), this head won’t engage.

Aftermarket replacement. This is a third-party part, not OEM Kobalt. It’s a direct fit for the listed models but may have slight differences in fit tolerance compared to the original.

Key Things to Know

• Quality concerns. With a 3.2/5 rating from only 10 reviews, expect occasional reports of plastic cracking or bump-feed mechanism jamming after moderate use.
• Installation is straightforward. Requires removing the old head and threading the new one on (counter-clockwise). No special tools needed, but a spanner wrench helps if it’s tight.
• Line loading can be finicky. The bump-feed design may require precise winding to avoid tangling. Follow the included instructions carefully.
• Check for wobble. Some users report slight wobble at high RPM. Tighten securely and inspect the drive socket for wear before installing.

Should You Buy It

If you have one of the listed Kobalt 80V models and need a cheap, functional replacement head, this will work. It’s not as durable as OEM, but at $21 it’s a budget stopgap. Skip it if you want long-term reliability or run heavy line for thick brush—look for an OEM or metal-bodied head instead.