Flat Telescopic:Flat Telescopic Limiter Stay
  The opening distance of limiter stay is relevant to installation position. The lower the installation position, the smaller the opening distance. According to window and door criterion, the opening distance of top-hung window shall be not more than 300mm.
  Symmetrical installation of each pair of limiter stays is required and tolerance within 1mm.
  Installation direction shall be consistent with graph showed, the bottom of limiter stay should be installed downward.
  When closing it, pull directly back are not allowed, you should push out first and then pull back to close.

Square Telescopic Limiter Stay
  The telescopic limiter stays apply to top hung window to restrict the opening angle.
  The telescopic limiter stay make the sash automatically lock at the designed position which contribute to wentilation, maintenance and protect the sash against strong wind.
  Loose the telescopic limiter lockable status by softly elevating the sash then close it.
  Comply with JG/T 128-2007 standards.