As of my last update in 2023, there is no widely recognized LEGO set with the precise number 4421 in the LEGO catalog or among enthusiasts. LEGO sets are typically categorized by unique set numbers that identify them within the vast array of products produced by the LEGO Group, ranging from small, simple builds to large, complex models suited for advanced builders. These sets span various themes, from cityscapes and vehicles to iconic characters and scenes from popular movies, as well as original creations designed to inspire creativity and imagination in builders of all ages.
It is possible you might have either a misprint or a mistaken set number. LEGO set numbers are specific and usually correlate to a unique product. If youre looking for information on a particular set, it might be helpful to double-check the set number. Alternatively, providing a description or theme of the LEGO set could help in identifying it correctly. If you have any more information or a different query, feel free to ask!