Immediately begin stabilizing your RV camper or toy hauler with the Dumble RV Supplies 2 Pack Heavy Duty Trailer Jack Leg Set. Once installed, you can simply flip down the 5th wheel stabilizer brackets and extend them to create support for the back end of your trailer. 2 by 4-inch (5.1 x 10.2cm) mounting plate attaches to your trailer bumper or frame using 3/8-inch bolts (not included). Be sure to double-check swing clearance and direction to ensure correct installation. To extend from 12 to 18 inches press the brake switch for natural extension, then use included handlebar to create leverage that will easily add more height. Folding stabilizer jacks can be used as camper leveling jacks, travel trailer stabilizer jacks, ATV and motorcycle trailer jack stands, and boat trailer legs. Warning: This product can expose you to chemicals which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm.