What the thread found

• PRO arm sockets are undersized and will fit in most vests on the market, but PRO vests with PRO socket blocks provide the best fit.
• Socket compatibility problems can occur when combining arms and vests from different manufacturers, with some combinations requiring mechanical adjustment or block replacement.
• Tolerances between socket blocks and arms can be tight enough to prevent removal, requiring filing, machining, or socket block replacement to resolve.
• Older vest models and early production socket blocks are more likely to have compatibility issues than current equipment.
• Klassen vests are reported to accept PRO arms without fitting problems.
• Socket block incompatibilities have been documented between various arm types and vest blocks, including instances requiring significant modification.

Depends on

• The thread dates from 2008 and discusses equipment from that era; current production may have different tolerances.
• No systematic testing across all vest and arm combinations is documented.
• Solutions mentioned (filing, machining, replacement) require technical skill or professional service.
• The original poster's specific EFP rig model is not identified, so compatibility cannot be guaranteed for all EFP systems.

Gear in this thread

G-70catalog

Parts

Hard Mount

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