Zer0's observant enough to know that this doodad has more than one function, but he doesn't have a chance to ask about it before Jacob's grabbed him and Legend of Zelda style hook shotted them up to another level. Zer0 doesn't really physically react or say anything, but a red holographic :) does pop up in front of his helmet.

He dusts himself off a bit and glances down over the ledge, "I need to get one. / Efficient way to travel, / saves a load of time."