What are the item drop rates for the Back & Kickin’ Brass event?

[NoknokHuzthayr]

Previously, item drop rates on events are once every 3.5 hours. However on the current event, I was able to get two items with just 30 minutes between them, and then another longer time period before I can get my next two items. What exactly are the time periods for the item drop rate?

 

[imnrk]

Ever since a previous update, we've been getting two drops per window - it's probably just more noticeable now that the drop windows are so much shorter.

 

[Barot8]

Is there a list (with images) of what the item drops could be? So far I've seen the squid mask, squid arm band, and squid backpack.