It automatically locks the spring at the maximum extension, with a simple movement it frees the sliding.
This safety device is recommended to avoid that in case of rolling or pitching a door can be inadvertently closed.
Body in stainless steel AISI 316.
N.B. :1) By adding the block the declared length of the spring is extended by 25 mm.
2) When mounted in pairs, order extension 38.040.90.