FLOCK 4A-18, also known as Flock 4a-18, is a CubeSat (3U) satellite launched by PLAN on April 1, 2019, from the Satish Dhawan Space Centre using a PSLV-QL launch vehicle. This technology demonstration satellite has dimensions of 0.3 meters in length and diameter, with a span of 0.3 meters. It weighs 5.7 kg both at launch and dry mass, indicating no significant change post-launch due to fuel consumption. The satellite is equipped with either PS0, PS1, or PS2 imaging payload named Dove 2215, which utilizes solar cells and batteries for power generation. Its mission lifetime is estimated to be approximately one year in an International Space Station (ISS) orbit and between two to three years in Sun-Synchronous Orbit (SSO). The satellite's shape consists of a box with two panels.