What the thread found

• A used second-generation PRO post can be obtained for approximately half the price of a new one and includes an underslung junction box with parts that are compatible with IIIA setups.
• Upgrading from a non-telescoping to a telescoping center post on an IIIA typically requires new power cables.
• The PRO post allows extension beyond the standard non-telescoping post, providing a meaningful improvement in height range.
• A MK-V post can be adapted for use on an IIIA with custom modifications.
• Several individuals in the industry have specialized knowledge in center post installations and modifications for this camera support model.

Depends on

• The discussion references specific individuals by name for service providers, which limits practical utility for someone seeking current resources.
• The pricing information is from 2006 and does not reflect current market conditions.
• One respondent offered a used original IIIA extendable post in unknown condition without confirmed specifications.
• The maximum extension requirements and realistic expectations for telescoping distance were raised but not definitively answered in the thread.

Parts

Donkey Box

Same gear or parts

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