I would usually refrain from posting an odd-ball eBay item listing like this but it looks like this seller is selling a 512k/1MB L2 cache stick as a Sonnet Tech G3 L2. Maybe they are mis-informed. I'm not trying to bash 'em.
I've yet to se a SonnetTech L2 card w/out the purple heatsink (it should be on the side that is shown in the pict I believe) let alone an "SDT" branded label sticker on it.
The seller looks like one of those orgs that sells other peoples stuff. I could be wrong. I'm guessing the original owner of the L2 G3 put the cache stick that WAS in their machine when they upgraded into the Sonnet box and now it's being resold as the G3 by mistake. I'd just hate being the one who buy's this and finds out that it's NOT the G3 card I thought I was bidding on.
To moderator: If this was an inappropriate post, let me know please.