One of the more expensive post op supplies required, it was also one of the more difficult to find. I ended up purchasing them on Amazon but the shipping was very delayed, so I advise getting beforehand.
The yellow stuff is the Xeroform. It was used on both my arm and leg, my arm was changed more often. I used the Xeroform for about 3 weeks on my arm, changing the bandage every 2 days after the first week. I went through around 14 packages of Xeroform for my arm.