I use the "thermal" drippers (Wildlife Research). They work by the heating and cooling of the container by the temp change from day/night. I found they used scent too fast so I plugged the ends and drilled an 1/8" hole and the scent would last for weeks. That way you can stay away from them longer. The thermal drippers are also great because they only drip in during the day. This helps to get the deer coming to them a bit more in daylight than in the dark. Deer know fresh.

Gotta remember that a scrape site is where a deer will be using it's smell to it's fullest extent so the recommended rubber boots (and gloves) areA MUST!

Good scrapes include the recommended licking branch and the site should be chosen to include a good licking branch.

I use a pair of the "extended pliers" (you know what I'm talking about? the kind you use to pick trash and stuff up with so you don't have to bend over) to place my bottles pretty high up in the tree. I use big fish hooks to hang them.

If you really want to see what your set-up is doing - game cam the site.