The Warp Pad is a gadget in Up Your Arsenal. It allows Ratchet to set a Warp Pad down on warp points, and teleport back to them whenever necessary.
The Warp Pad is granted to Ratchet by the Galactic Rangers after "Help the Galactic Rangers", in which Ratchet assisted them Aridia during the Operation: DEATH VALLEY battle against the tyhrranoids. He used the Warp Pad in Qwark's hideout on the Thran Asteroid Belt to during "Find Captain Qwark", where he used it in conjunction with an elevator and to bypass a forcefield.
Behind the scenes
The Warp Pad was designed very early on in development by Mike Stout. The original design was that the player could throw out a disc and use it to teleport anywhere. As the developers believed this would be easy to implement, they left it until the last thing. However, though it was easy to program the Warp Pad itself, the ramifications of its inclusion were much trickier, as it broke levels by allowing the player to easily break level geometry and access areas they were not supposed to. Since it had been implemented late in development, and the levels had not been designed to account for its inclusion, there was no time to fix it, giving the developers the choice to either severely limit it or cut it entirely.
The limited version of the Warp Pad ultimately remained because Insomniac wanted to still require that the player complete Aridia before the Thran Asteroid Belt, and because there had been some planning around its inclusion still. One of the challenges on the Thran Asteroid Belt would have appeared at the very start to cross a pool of ice water, and was replaced by a platform as this original challenge did not work.