Every 1.5Ah and 2.0Ah pack in my garage arrived the same way, bundled inside a kit box with a tool I actually wanted. For years they sat in a bin while the 4.0Ah batteries did the work. Sorting through which ONE+ packs are worth buying is what finally changed my mind about them. A compact ONE+ battery holds a single row of five lithium-ion cells. The high-capacity version stacks a second row underneath, which raises the current ceiling and adds close to half a pound under your grip. On tools that never approach that ceiling, those extra cells do nothing except make the tool longer and heavier. Four tools in my collection run better with a compact clipped on.