apparently SPF is Sun Protection factor. The SPF numbers, multiplied by 10, indicate the number of minutes that the protective effects of the sunscreen or Sun Block with last. i.e. SPF 30 lasts 300 minutes, or 5 hours.

My skin has tanned easily and I have been using SPF 50 but still got tanned quite a bit.

Any recommendations which brand of sunblock is good? My assumption is that the UV protection is good already... just hope not to get so tanned so fast.

sunblock and long sleeve and straw hat, that's what i do.

Spf will prevent ur skin from getting harm by uv rays but it wont prevent u from getting tanned. Sun block lotion maybe. Spf 30 is more than what we need in singapore to protect ourselves. Any higher spf and u are just paying premium. Places like australia require abt 50 spf

Seriously sun block itself is not enough. long sleeve and cap would help but must endure the heat!

the best sun block i have used is the one provided at nsrcc locker room.
always applied generously before i head out for a round of 18 holes.
i do not feel so burnt-out compared to other brands after golf.
its called royal-sun if i remembered correctly, but i have yet to find it in retail stores.