You can order these Spring for Hurd Windows and many other window brands. Replacement window springs used on many single hung and double hung windows jamb liners. Each spring will come with a Clip as shown in picture. Clip is removable if you do not need it on your window.
Spring is 3/8" Diameter outside to outside
Wire diameter or gauge is as follows and is commonly associated with these color tips on the springs themselves: Red .041, Green .044, Yellow .047, Black .048, Purple .051
To Order By Spring Length Inches : Measure from tip of Eyelet to tip of Eyelet on spring. (Eyelet is the round bent out part of the spring located at both ends).
Due to the multiple sizes springs come in we do not stock spring. All springs are special order with a 1 - 3 week lead time. NO RETURNS for springs as they are special order.