FP MFG Painkillers socks are embedded with Artilage (Artificial Cartilage Foam) in the shin and ankle bone areas to protect from shinners... Artilage is a unique type of memory foam that becomes firm when impacted therefore allowing the socks to be comfortable and form fitting like a normal sock while still being very protective.
I wear these every time I skate. The fit is a bit stiff when you first put them on but once the warm up a bit they feel like a regular sock. They provide just enough protection to stop things like scraping your shins against obstacles/board and have enough stopping power to negate minor/medium shots to the shins and sides of your ankles. This will save you from ending a session over a couple of small hits to the area that would normally happen, without feeling rigid or in the way. I bought these because of switch blunts coming down and smashing the sides of my ankle and so far they have worked perfectly.
Package came with a large sock and a medium sock. They are two different sizes. I thought i was going crazy when i first put them on. But I will contact Footprint and they will fix it. Oh and they are comfy socks too. Takes a little bit to get use to the ankle and shin pads, but they do work.