Test item: 7 days under 313 light (equivalent to 1000 hours under UV from sunlight)
Sample from another Chinese manufacturer
The surface got yellowed obviously, due to the low-quality gel-coat they use.
Sample from a German manufacturer
The surface color got a little deep comparing with its initial state.
Sample from TOPOLO
The surface color got deepened even less than the German sample, due to the high-quality gel-coat technology in TOPOLO!