• The end posts are 21 3/8 inches high. If your window opens above that, you will need to use a window stop to keep your window from opening above the guard. You could also use a vertical style guard, which covers the entire height of the window. Double hung window guards can not be stacked on top of each other. Contact Automatic Specialties for assistance with stackable guards.
  
  
• All double hung window guards come with 4 horizontal bars. These bars telescope to fit various window widths. The example below is the 2335 model, which expands from 23 to 35 inches.
  
  
• There are 6 widths available, see chart below. If your window width falls right on the edge of a range, it is better to go with the guard in the larger width range. For example, if the width you want to cover is 23 inches, go with the 23 to 35 inch model (2335-44H).

• The "-44H" refers to the number of emergency release buttons and number of bars, respectively. There are 4 emergency release buttons per guard. The H stands for horizontal.
  
  
• Designed to conform to the safety standards for window fall prevention devices set forth by the American Society for Testing and Materials (ASTM F2090-01a), and recognized by the U.S. Consumer Products and Safety Commission.

• The end posts are available in three widths within each height range: 13 inches, 17 3/8 inches, and 21 3/4 inches (see chart below). You may need more than one guard to cover the width of your window, click on How to Order and follow instructions to determine the appropriate model numbers. The vertical window guards can be installed next to each other.
  
  
• Vertical style guards come with 3, 4, or 5 vertical bars and these bars telescope to fit various window heights. The examples following are the 3558 model, which expands from 35 to 58 inches high.
  
  
• The last two digits in the model number stand for the number of emergency release buttons and number of bars, respectively. For example, the 3558-43V model expands 35 to 58 inches in height, has 4 emergency release buttons and three bars. Vertical style guards have 4 emergency release buttons. The V stands for vertical.
  
  
• There are 6 heights available, see chart below. If your window height falls right on the edge of a range, it is better to go with the larger height range. For example, if the height you want to cover is 23 inches, go with the 23 to 35 inch model.
  
  
• Designed to conform to the safety standards for window fall prevention devices set forth by the American Society for Testing and Materials (ASTM F2090-01a), and recognized by the U.S. Consumer Products and Safety Commission.

Never mount telescoping bars horizontally in a sliding or casement window!

• Telescoping bars can only be mounted horizontally in double-hung windows. When mounted horizontally in sliding and casement windows, the window guard can act as a ladder and greatly increase the risk of an accidental window fall.

• For casement and sliding windows, guards must be mounted with the telescoping bars in a vertical position. Refer to installation instructions and specifications below for these types of windows.