Hi, I already use solder sleeves like these:
I have these https://www.digikey.ca/en/products/detail/te-connectivity-raychem-cable-protection/642145-000/573472
but am looking for closed end sleeves, where you put both leads on the same side and the other end is closed.
like this https://www.schmitt-neumann.de/en/produkte/product_detail_anschlusstechnik.php?id=243