This Lancer Systems extension tube (mfr. part no. LSX3XM) adds 3 rounds of capacity to a Mossberg 590 shotgun’s magazine tube. It measures approximately 9.2 inches and combines machined aluminum components with a lightweight carbon-fiber tube.

Key Specifications

• Adds 3 rounds to your Mossberg 590’s magazine capacity.
• Fits the Mossberg 590.
• Overall length of approximately 9.2 inches.
• Combines machined aluminum components with a carbon-fiber tube.
• Includes an extra-long spring that can be cut to optimize loading.
• Extension clamps are recommended if the tube extends beyond the barrel.
• Manufactured by Lancer Systems.

Frequently Asked Questions

Do I need to cut the included spring?

The spring included is extra-long by design so it can be trimmed to match your specific installation for optimal loading.

Is a clamp required for installation?

Lancer recommends an extension clamp if the tube extends beyond the end of the barrel.

Buy the Lancer Mossberg 590 Extension Tube

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