This is a preorder, estimated time of delivery is 2 months (~60 days) from end of preorder period.

The preorder period will last 2 weeks, will end Sunday night, November the 15th at 11:59pm est. After that, all the components will be ordered and should take about 60 days to arrive. Your orders should start shipping soon after the 60 days are up.

Upgrade your Annex Engineering K3 from stock 9 mm belts to stronger, stiffer 12 mm belts with this precision SLM aluminum kit.

Manufactured via Selective Laser Melting (SLM) in aluminum, these parts are fully tapped and ready to install. They deliver a significant step up in rigidity and durability compared to printed plastic versions—ideal for higher speeds, accelerations, and long-term reliability.

What’s included

• XY rail brackets / tensioners
• Rail holders
• All parts tapped and ready to go

Key details

• Designed for 12 mm belts (upgrade from the K3’s stock 9 mm belts)
• Optional upgrade for the Hula toolhead—you can still print the plastic versions if preferred
• based on the excellent work by Mathematical Potato.

Preorder notes

• Ships together with the Hula if ordered at the same time
• Standalone orders: approximately 1 month lead time after the end of the preorder period

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