Budget Canon telephoto zoom, cheap but optically weak and widely bundled with entry DSLRs.
The Canon EF 75-300mm f/4-5.6 III is Canon's entry-level telephoto zoom, produced since 1999 and bundled with countless Rebel and xxxD-series DSLRs. It covers 75-300mm on full-frame or 120-480mm equivalent on APS-C, making it a popular first telephoto for beginners on a budget.
Optical quality is the weakest point. Sharpness is acceptable at 75-200mm stopped down but deteriorates badly above 200mm. Heavy chromatic aberration is visible in high-contrast scenes. There is no image stabilisation. Autofocus uses a micro-motor that is slow, noisy, and hunts in low light. Build quality is all-plastic.
Canon EF mount with a 58mm filter thread. Multiple variants exist including the III USM with faster AF and the II USM. There is no IS version of this focal range. The EF-S 55-250mm IS STM is a far superior alternative for APS-C users.
Extremely cheap used. At this price it is almost disposable. Check that autofocus works as motor failure is the most common issue. The EF-S 55-250mm IS STM is a dramatically better lens and the recommended alternative for anyone shooting on APS-C.