Successfully completing a single Biker Business Sell Mission (including Weed sales) will grant you the White High Brass Tee. Meanwhile, completing any Short Trip gets you the Black High Brass Tee.
Flood the black market by selling over 100 000GTA$ worth of product in Biker Business Sales to complete the Weekly Challenge and you’ll be rewarded with an extra 100 000GTA$ and the 4/20 Cap.
