A fuel vapor canister is presented, comprising two or more pneumatically coupled concentric adsorbent beds, a vent port configured to deliver fresh air to an outermost concentric adsorbent bed, and a purge port configured to couple an engine intake to an innermost concentric adsorbent bed. The concentric adsorbent beds facilitate improved purging of the canister, thus decreasing bleed emissions. The concentric adsorbent beds may have a bi-conical structure yielding a conical flow path which allows fresh air to flow through the adsorbent beds equally, reducing the size of a canister heel.