Are you planning to buy window sill locks, and are you confused about the options ? This page is just for you.

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Our Top Picks:

Best Overall: Buy: Defender Security Window Sill Lock READ REVIEW

Best For Mobile Home: Buy: Shop Square Window Sill Lock READ REVIEW

Best With Key: Buy: Maxdot Window Sill Lock READ REVIEW

Best With Slider: Buy: Defender Security Screw Part READ REVIEW

Best For Great Price: Buy: Momentum S Window Sill Lock READ REVIEW

Best For Customer Service: Buy: Tahikem Window Sill Lock READ REVIEW

Best For Fast Delivery: Buy: Lockit Blockit Window Sill Lock READ REVIEW

Best For Kid: Buy: Maxdot Key Handle READ REVIEW

Best With Tracks: Buy: Jeacent Window Sill Lock READ REVIEW

Best For Universal Fit: Buy: Primeline Window Sill Lock READ REVIEW

Best Overall: Defender Security Window Sill Lock

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The Defender Security Window Sill Lock's high-end materials makes sure that it ages well with use. And, the defender security window sill lock is cost effective, It is perfect for vinyl windows and has a great design. Make sure this fits by entering your model number. This sliding window lock is constructed of extruded aluminum with a steel thumbscrew, and it comes in a white painted finish. Finally, the defender security window sill lock comes in versatile white painted color.

Almost all customers found that the lock is a simple tool for a simple job. In addition, they also found that the lock is good for residential window. Overall, many have used the defender security window sill lock for more than a few months without any complaints, and it shows no sign of giving up.

• These are perfect at a very affordable price.
• This works well. It is worth the money and has a better design.
• Extruded aluminum construction with steel thumbscrew.
• This provides great value and has a perfect design.

Best For Mobile Home: Shop Square Window Sill Lock

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Compared with other locks in this category, the Shop Square Window Sill Lock has a convenient design. The shop square window sill lock is perfect for vinyl windows, feels safe and it is very strong. Use this window lock to protect your family from intruders and more. These window locks are easy to install with double door lock thumb screws securing sliding door & window tracks up to 3/16" wide with the rubber insert or 3/8" without the rubber window seal.

The lock is designed to work with sturdy metal frames. Further, the lock is very simple, is black and it has added extra security. Finally, the shop square window sill lock is good for window lock security, feel safe and it is worth the money.

Almost all buyers found that the lock does take 2 per window to fully secure it. Further, they also found that the lock is a great temporary fix for a broken window latch. In conclusion, at the price, they believe that they got a steal of a deal with it.

• This is ideal for securing a vertical window air conditioner or window fan setup.
• This is very effective and it is very secure.
• These fit a variety of window frames and are padded to protect the frame itself.
• This adds more grip & protects the window frame from getting damaged.

Best With Key: Maxdot Window Sill Lock

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If you want nothing but a lock that is satisfactory, this Maxdot Window Sill Lock is certainly the best investment. The maxdot window sill lock comes with a great window and it is made of durable material. Maxdot 4 piece sliding window locks stop aluminum alloy door frame security lock. In addition, the lock does not need to install extra tools, it equips a hex key in each window locks, holding on the track by key control.

The lock does the trick, provides for great security, It is perfect for security locks and has a great design. Finally, the maxdot window sill lock can be easily applied to most environments.

Almost all buyers quickly discovered that the lock is easy to undo from inside. Further, they strongly agree that the lock comes with a key and is easy to install.

• This can work on a sliding mirror closet.
• This will take effort to remove.
• This provides great value, it has a nice and has a perfect design.
• This is designed for sliding windows.

Best With Slider: Defender Security Screw Part

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We know from years of feedback from readers, amazon sellers, and family and friends what most people want in a convenient and appropriate lock. The Defender Security Screw Part is exactly that - it's a simple lock that hits all the right notes. The defender security screw part is safe, is best for good fit and it is reliable. Finish by tightening the thumbscrew with pliers to securely lock windows in closed or ventilating positions. Further, this is made with fast shipping, is reasonable and it provides great security.

Most importantly, the defender security screw part can be bought for good value and it fits well.

Most buyers found that the lock is quick and much easier than taking it all the way off. In addition, they strongly agree that the lock is easy to install and a great addition to existing home security. And, they also found that the lock is easy enough to install, but they are too small for most window tracks.

• This will move with applied pressure.
• This can slide back & forth with the loosening of a screw.
• This comes with a nice natural finish.
• This comes with a steel thumbscrew for use on metal horizontal sliding windows.

Best For Great Price: Momentum S Window Sill Lock

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Compared with other locks in this category, the Momentum S Window Sill Lock has a convenient design. The momentum s window silllock works as advertised, is highly recommended and it is very secure. Make sure this fits by entering your model number. Further, this is compatible with 7 x 6 x 1.7 inches.

Finally, the momentum s windowsill lock feels safe, is attractive and it is made for easy installation.

Most customers opine that the lock takes a split second to loosen a screw and pull it out. Also, they strongly agree that the lock fits on 99.9 percent of all windows. In addition, they strongly agree that the only thing to remember is that the lock needs to be removed if the window needs to be used as an emergency exit.

• This is great for peace of mind.
• This is easy to install and take off when needed.
• This is great as a precaution, be careful with local codes and adequate fire escapes.
• This is good for an excellent price and it works perfectly.

Best For Customer Service: Tahikem Window Sill Lock

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The Tahikem Window Sill Lock is the most reliable lock on the market today. The tahikem window sill lock is built with high-quality material, has a strong grip and it is reliable. You can use the key wrench to slowly rotate the screw nut to secure it on the window track. The window safety lock is made of aluminum alloy, durable and sturdy.

Most importantly, the tahikem window sill lock is very convenient and it fits perfectly.

Almost all customers quickly discovered that the lock is easy to use, tough for kids to mess with. Also, a few say that the lock is easy to install and hold well when they’re on. Further, a few also found that the lock holds the windows securely ( horizontal slider type ) and there 's no way for them to get them off without the included tool.

• Manufacturer says: we will reply within 24 hours.
• It ensures your family members ' safety.
• This is very effective, fits well, it allows for easy installing and has a better design.
• This match for white sliding windows, sliding doors and vertical doors.

Best For Fast Delivery: Lockit Blockit Window Sill Lock

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The Lockit Blockit Window Sill Lock's material feels more premium than its price would suggest. The lockit blockit window sill lock is suitable for heavy duty material and it is made for horizontal windows. Control how high you want the window to open with the 13 adjustable settings. The lock - it block - it offers an added layer of home security that allows the elderly to live as they want and reduces their concerns of being insecure.

The lock is easy to adjust and it is highly recommend. Lastly, the lockit blockit windowsill lock is present, fits perfectly and it is reliable.

Most customers quickly discovered that the lock is great for keeping windows closed, can also be used as a beating stick. Also, a few say that the lock does take some effort to pull the device free. In addition, a few say that the bar is of good quality and is very easy to install. So, buyers were eager to recommend it to friends and families.

• It is highly recommended to leave your window open more than 6 inches max.
• This allows for windows to be locked open from 1 inch or more.
• This is strong enough and it is easy to assemble.
• This will be strong and hold up well.

Best For Kid: Maxdot Key Handle

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Compared with other locks in this category, the Maxdot Key Handle has a convenient design. The maxdot key handle is great for a great price, It works as expected and has a perfect design. Open the screen window when the weather is hot in summer, which can improve air circulation, You can use the window locks to fix the screen window, It can prevent children from falling and prevent thieves. Also, it is equipped with a hex key, spinning the key slowly through the hole, just holding on the track by key control, no additional installation tools.

Lastly, the maxdot key handle is present, has a strong grip, it is used for necessary items and has a better design.

Almost all customers opine that the lock comes with a clear plastic plate to protect frame material from the screw. Moreover, a few also found that the locks are older and have a thicker trim. To sum up, many have used the lock for more than a few months without any issues, and it shows no sign of giving up.

• This is great for child safety.
• This is good for preventing break - ins.
• This is easy to install/remove since windows or slider doors can need opening often.
• This can also be used on double - hung windows.

Best With Tracks: Jeacent Window Sill Lock

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The Jeacent Window Sill Lock is specially designed for your daily purpose and has all useful features. The jeacent window silllock is constructed with steel construction, is highly recommended and it makes for great security. Keep your window at a height to stop your ac unit from falling out or being stolen from outside. This a / c window security bar is specially designed to keep windows staying at a safe height / width and locked, preventing the air conditioner from falling out of the window when installed.

The lock provides it with a longer longevity and makes it harder to break off or deform. Also, it is used for vinyl windows, It works perfectly and has a unique design. Most importantly, the jeacent window sill lock works well with most standard window tracks with air conditioner installed.

Most customers opine that the lock is expandable exactly as described. In addition, a few strongly agree that the lock is made of strong materials.

• This is easy to use and does what it says it does.
• Press the buckle and adjust its length to your needs.
• This can break the window lock adjusted from 10" to 17.5" in length.
• This is made of two high-impact steel tubes for sturdy and stronger protection.

Best For Universal Fit: Primeline Window Sill Lock

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The Primeline Window Sill Lock's material feels more premium than its price would suggest. Further, the primeline window sill lock is inserted into the keyhole, the thumbturn and cam are released, allowing it to be rotated open or rotated closed. Keep curious children safely inside with prime-line’s child-proof keyed sash lock. This child - proof sash lock is strong, durable and made to last longer than the toddler years. Most importantly, the primeline window sill lock is sold in exquisite white color.

Almost all customers found that the lock was only one item for this price. Moreover, a few say that the lock is made for windows with a narrower surface area. In addition, they also found that the keyed child - proof lock works + it is very easy to install.

• This can only be opened with the included key, keeping curious kids safely inside.
• This makes for easy installation and it fits perfectly.
• This is designed to child-proof sliding windows and secure windows at high elevations.
• This is perfect for great quality and it is worth the money.