SIM&NAT Auxiliary Durable Window Lock For Sash Window Or Sliding Window With Rubber Covered,Adjustable Window Sash and sliding Stopper With Steel Screw,2 Pack Improved air circulation in a confined areas with limited window size,as well as keeping your child safety(like pinching the finger or falling off) and preventing you from the crime. Keep your window opening but home safe when you are on vocation,applicable for sash window,sliding window,sliding door,bathroom,children's room Improved prevention effect with double use at the terminal sections.Both use in keeping the window closing and partial-opening,adjustable length with steel screw for easy using. Attachable area:1,Maximum(Inner Length:1.3in,Outer Length:1.69in).2,Minimum(Inner Length:0.59in,Outer Length:1.02in).Inner Length Ranger:0.59in-1.3in,Outer Length Ranger:1.02in-1.69in.(See left-hand picture,Please confirm it before you place an order) Covered with rubber,increase the friction for the better use and would not damage or scratch your window(More information about the product,please see the description below)