+10 MAB for ice spells for EACH ice weather and ice day. up to +30 MAB for double ice weather, ice day...and they STACK for MAB.
With BLM af2 legs, and macro your zenith gear in with a sorcerer's ring to reduce HP (need to have HP equal to that will be in yellow with no gear on...so yes you CAN have white HP and still get the +10 MAB from the ring. I know the cap for this on hume was 728 HP for BLM) giving you up to +75 MAB with moldavite earring, Zenith mitts, weskit and full ice potency merits. INSANE dmg. Trust me.
ALSO will decrease resistance for ice spells by 10% added with an Aquilos staff giving a minimum of 25% less resistance on Bind and Paralyze and give + magic accuracy during ice weather/day for nukes...(yes the staves DO increase damage --NQ 10% HQ 15%--AND give you + magic accuracy for spells using that element.)
To get the reward Hyorin Obi in the quest "In the In the Name of Science." you trade Yurim (First Floor, Tavnazia) a Silver Obi, clear chip, and Xzomit Organ, and Phuabo Organ.
this only works for spells so far frrom what i have seen. Here is a link showing the wind obi does not work for equipment. http://ffxi.allakhazam.com/db/jobs.html?fjob=10&mid=1116055437155823749&num=16