Kester 44 Rosin Core Solder 63/37 .020 1 lb. To attempt. So far I've only used Radioshack Silver Bearing Lot 62/36/2. Having used this Kester 63/37 all I can say is this solder is amazing! Perfect for all my projects. I work a lot with SMD and IC and this solder works very well. I can't see much of a difference between this and the silver stock and will be using this solder from now on. Don't hesitate to buy this product, you won't be disappointed!