Each type of gate will have a different kind of locking mechanism. The one condition that you should make sure of before purchasing and installing a pet gate is that you can open it easily, even while burdened. The mechanisms often vary between the types of pet gates. Freestanding gates often don't have any locking apparatus and are used to block off areas you want to remain pet-free. Pressure mounted gates use the pressure from a spring to create tensile force and keep the gate sturdy. Depending on how strong your gate and how thick the spring, some of these may be trickier to open than others. Mounted gates come with an array of locking mechanisms. To pick the perfect one for your pets and home, think about how you will most likely be using the gate. If it is in a high-traffic area and will be opened and closed often throughout the day, you may need a gate easily opened with one hand. If you have an escape artist for a dog, you may want something with more resistance to prevent them from getting loose.