Motors with a stator diameter of 16 to 20 mm – for example 1604, 1606, 1804, 1806, 2004, 2006 and 2008. Sizes 1604 and 1606 are designed for 3.5" builds, while 1804 and 1806 are for lightweight 3.5–4" freestyle and long-range drones.
Motors from 2004 to 2008 are typical for 4" freestyle and long-range drones and lightweight 5" builds. On 6S, roughly 1,700–2,500 KV is usually chosen, while on 4S approximately 2,800–3,500 KV.