Milwaukee Batteri M18 B4; 18 V; 4.0 Ah; Li-Ion

Both products are 18V Li-Ion batteries ideal for use with power tools, making them a solid choice for consistent energy output. However, the B5 offers a higher battery capacity of 5.0 Ah compared to the B4's 4.0 Ah, providing a longer running time for demanding tasks. Despite this difference in capacity, both batteries are otherwise similar in terms of voltage and type. The choice between the two depends largely on the user's need for longer usage time on a single charge versus potential cost considerations. Those seeking extended runtime might prefer the B5, while others might find the B4 adequate for lighter tasks.