Adopt un-symmetry arm:

The arm is credible locking structure:

Technical Parameters:

Features:

• Safety unit of two columns is released by one switch controlling.
• Lifting movement with hydraulic power on one piece formed steel post.
• Double safety with self-locking devices on lifting chain and cable on both posts.
• Adopt mechanical height limited safety devices.
• Adopt un-symmetry arm to make lifting movement reliable.