1.1. Sturdiness:The security door lock solid,well made by thicken Znic Alloy with perfect satin nickel finished, anti-rust,durable and strong.Passing 72-hour spray test while the industrial standard is 24-hours,our products a longer life span for 8-10 years in normal conditions. 2.2. Home Security&Childproof Reinforcement:This product a bit of protection against home invasions where someone knocks on your door asking for helps and then forces their way in.If you must answer the door,keep this latched and open the door just enough to speak to them.This latch installed at the top of the door will allow toddler to open the door but not go through.This now prevents toddler from falling down the stairs.So this is the perfect solution to get childproof the front door. 3.3. Advanced Craft Features: This latch is far simpler and does a far better job. It has a spring and pin system that locks it in 3 different positions. Latched, straight out, and open. So, 0, 90, and 180. Simple yet effective. 4.4. Safety Door Lock Design: The action of the flip-bar is very smooth. There is a notch-feel at about the half-way point so you know when you're latched or not. There is sufficient stiffness that you don't feel like the latch is just flopping around and you know it will stay in place wherever you've moved it, but it is still easy to flip back and forth.