Generic brand 11 watt UV globe

UV globes should be changed every 12 months. Although they may still be producing light, the wavelengths change significantly, meaning the UV component of your filter diminishes over time.

233mm in length

Suits OASE Vitronic 11 and Filtoclear 3000, 6000, 11000, 15000 plus many more filters.  Check what your filter requires