Pinning an effect to beginning and end of Keyframe-Premiere Pro

So I am often adding effects or creating a lower third but when i stretch them out to make longer, the effects stay put. But I have seen people pinning effects to the beginning and the end.  I would like to make the graphic once and not have to move the keyframes if I need to make the graphic longer. I am not even sure of the proper teminology so I apologize in advance.

Thank you