Want to use a refill in a Sherpa pen but it's a bit short? No problem, just pick up the Sherpa Extension Spring and use it to make up the gap.
Classic Sherpa - Just drop into the barrel and use the Sherpa Pen like normal. It will automatically adjust to the shorter refill.*
*Please be advised that the extension spring can get tangled with the original spring. If this happens and you need to remove the extension spring you will need to use a paperclip fishhook to extract it.
Ballpoint Sherpa - Insert the refill you want to use in the Sherpa body and then insert the Extension Spring behind it. Screw the back end on until snug.