This listing contains many types and sizes of springs. Very strong material as these were recovered from  vintage locks, only the spiral double end loop is new as well as the dial cord tension spring.

Flat material (various lengths) is used as a "return or hold" replacement spring in vintage mortise and pocket door locks - see pix for an open lock showing a flat spring (vertical in the picture) holding the tumbler down. You'll know what I mean once the lock is taken apart and either the spring flies out of the lock and you can't find it OR the spring is just missing and you have to make a new one.

Offset spring can be used on a variety of lock functions. Flat springs are generally used in the upper and lower part of the lock to keep loose parts under tension such as the spindle pivot or the lock tumbler. All dimensions approximate. Flat springs with offsets are not made to any specific angle as the offset just hooks into the casting position posts. Some are made from reclaimed material.

On the spiral spring with loop ends, use a needle nose pliers to re-form the end loop to fit the lock attachment points.

My method of making one to length involves a vise. Place material in jaws after determining the length required (maybe a little extra), tighten the vise securely and hold the material at the base and move it back and forth until it snaps. Always wear eye protection and gloves. Sharp edges may occur. Smooth out with a file.

Special 3/8 x 1.5 is YALE - see pix. 10-24 x 1/2" slotted, oval knob to spindle screws - in bright brass or aged finish to match your application.

If questions, send email along with picture of the application, if possible..

Measure thrice - buy once.