This Lancer Systems extension tube (mfr. part no. LSX6XM) attaches to the existing magazine tube on a Mossberg 590 shotgun to add 6 rounds of 12-gauge capacity.

Key Specifications

• Adds 6 rounds to your shotgun’s magazine capacity.
• Fits the Mossberg 590, 12 gauge.
• Combines machined aluminum components with a lightweight carbon-fiber tube.
• Includes an extra-long spring that can be cut to optimize loading.
• An extension clamp is recommended for tubes extending beyond the barrel.
• Overall length of approximately 14.5 inches.
• Manufactured by Lancer Systems.

Frequently Asked Questions

Is this a standalone magazine?

No, it’s an extension tube that threads onto your Mossberg 590’s existing magazine tube to add 6 rounds of capacity.

Do I need anything else to install it?

An extension clamp is recommended if the tube extends beyond the barrel; the kit includes a cuttable spring.

Buy the Lancer Mossberg 590 Plus-6 Extension Tube

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