There are plenty of RV Park type campgrounds out there.  However I like the scenic view and smells of a wooded campground.  There's just one problem with these.  In my area of the country, these are usually built on a ridge and the pads aren't always as level as they could be.  For owners of most larger rigs, you know well that the stablizer jacks have NO ability to level a trailer that isn't level.  Enter the Camco Tri-Levelers.  Back your trailer into within 18" of your intended final stopping point on the pad.  Lay a pair of these right behind the rear tires of the trailer, making sure their parallel with the tires.  Back up until you've achived your desired height.  On asphalt these will not move.  Then use a pair of standard chalks to chalk the front tires.  After that, your set, drop your trailer and set it up.Why do you need them?  Of course, camp long enough and you'll see everything from people driving their trailers onto 2x8s to slabs of concrete.  These are MUCH safer, will not rot, will not slide, and will not crack.  They are study and made of think ridged plastic.  Each one I would say weighs about 5 lbs so they'll still be lighter than anything else you carry.  And they will last forever!  You could safely leave these under your rig for years without worrying about damage from weather or sunlight.Why not 5 stars?  Three reasons...  1) It's not safe to use these on your own without a spotter.  An experienced RVer can back his rig onto a pad with no assistance.  However with these it's just not safe.  You could easily back off the back edge since the rear lip is no taller than the ones to each tier of leveling.  2) These are only suitable you rearward sloping pads with minimal side-to-side slope.  Due to the face that these are only 18" long they cannot level a tandem axel trailer from side to side as both axels will not touch the leveler.  And they are too long to fit a second Tri-leveler under the front tire for standard trailers.  Though side-to side leveling would be possible for single axel trailers.  3) Final placement is important as it could damage your tires (especially if being left for a season.)  When I use them and the trialer is still hiched it pinches the tire.  After leveling this seems to go away.  But if it didn't and you were concerned for your tires, this would mean rehitching and adjusting.  Each level is only about 5" long by approximately 9" wide.  So tire contact can be an issue.  For more agressive slopes, my recommendation after using them a couple of times.  Drive you rig onto them until the rear of the chock (whichever level your using) is pinching your tire.  And making sure you don't drive off the back!  Then when you let the tongue down it will stop pinching and sould be just right.Final thoughts...  These levelers are purpose built for the most common type of leveling.  They do very well at that.  They don't do well with other types of leveling.  Though I suppose you could use them with a foward slope as well if you were creative with your tongue jack.  If it seems like I'm being critical of them, I'm just trying to give an honest review.  I do think they are a great, well built product that is worth owning if you enocounter this type of issue with your trailer.  If you have issues with side-to-side leveling, there are other products out there that will suit you better as well as cost you more.  Personally I own both since I never know what type of situation to expect.  I like the simple design.  No assemlby means they're easy to move.  Unless the situation requires it I will always grab these first for just that reason.  One final thing to consider.  Anytime you raise a tire or pair of tires on your trailer you're obviously going to have a more significant rise on the end of your trailer.  Make sure your carrying something to let you sill use your stablizing jacks.