The Canon Extender EF 2x II is a 2x teleconverter for the Canon EF autofocus mount, doubling the focal length of compatible EF telephoto lenses while costing two stops of light. It sits in the second generation of Canon's EF extender line and is aimed at sports, wildlife and aviation shooters who need extra reach without carrying a longer prime.

UK auction activity on this extender has been thin, with one verified hammer result of £94 in September 2025 — a wholesale saleroom price rather than a dealer asking figure. On that single data point the median and the range sit at the same £94 mark, so as of 2026 a clean copy is broadly worth what that lot fetched at auction; expect dealer retail to be appreciably higher once commission and warranty are layered on top.