The Jellyvader Cap is Headgear in Splatoon 2. It is a 3-star item produced by Skalop and comes with the main ability Ink Saver (Sub).
It can be purchased from Headspace for 10,000 or from SplatNet 2 for 15,000.
The Jellyvader Cap is a black leather flat-bill cap. On the front are two light blue, pixelated jellyfish.
The Jellyvader Cap comes with Ink Saver (Sub) as a main ability when purchased from shops or ordered from Murch. When purchased from SplatNet 2, this item can have any other Ability normally available to Headgear items.
As a 3-star item, it also has three slots for secondary abilities. Since it is made by the Skalop brand, it has a higher chance of rolling Quick Respawn and a lower chance of rolling Special Saver.