The Special 304 Key Release (1.7 m) is an external manual Cable Release override system designed for automated garage doors. It allows the user to be disengaged the clutch from outside the building using a key, enabling manual door operation during:

• Power failures
• Motor faults
• Emergency access situations

It is typically used where no secondary pedestrian access door exists.

• “Special 304 – External manual release for sectional doors up to 1.7 m & 2.5 m”

Key Features

• External emergency override via key cylinder
• Designed for garage doors
• Compatible with Marantec and similar operators
• Enables safe disengagement of drive trolley
• Includes pull cable system (1.7 m length)
• Weather-resistant lock housing
• Simple mechanical operation (no power required)

Technical Specifications

How It Works

1. Insert key into external lock cylinder
2. Turn key to release mechanism
3. Pull cable disengages motor carriage
4. Door can now be opened manually

Commonly used with:

• Domestic garage door openers
• Industrial sectional or roller doors

Safety & Compliance Notes

• Essential for emergency egress/access compliance
• Prevents forced entry damage during outages
• Should be installed at accessible height
• Key control is important for security