The Scotty Mini Power Grip Plus 1181 Downrigger Line Release Clip is fitted with an 18" wire leader and a cannonball snap that clips onto your downrigger bomb.
If you want to run another bait at a different depth with a second rod setup, get a 1180 Line Release Clip and attach it to your downrigger line at the desired depth, it will hold at that depth and won't slide up or down it.
Let's say you wanted to run a bait/lure at 15m and one at 10m to cover more ground, on the downrigger bomb you'd attach one of these 1181 Line Release Clips as normal from one rod, lower the bomb down into the water and 5m later you'd attach the 1180 Line Release Clip which will grab and hold the line at the shallower spot, then you lower it to 15m.