This article explains what the Top Tether does, and introduces how the third point works and where the Top Tether anchor point is commonly located in a car.
What is the ISOFIX third point?
In most cars with ISOFIX, there is also a third point, also known as a third anchor point. The location of this third point may vary depending on the car brand or model. In general, the ISOFIX third point may be located on the upper or lower part of the car seatback. Some cars may also have a “Top Tether” label to help you identify it.
At PERO, we refer to the ISOFIX third anchor point as the “third point.” In some articles, you may also see more technical terms such as “third anchor point,” “child car seat third anchor point,” or “ISOFIX third anchor point.” These all refer to the same third point.
Common Locations of the Third Anchor Point in a Car
Common Location ①
Behind the left and right rear seats, between the middle and lower part of the seatback.
Common Location ②
Rear seat ceiling.
Common Location ③
In the trunk, on the upper or inner side of the trim panel.
Common Location ④
Behind the rear seatback panel. Open the panel to find the anchor point.
Common Location ⑤
At the base of the seat. Fold the seat forward to find the anchor point.
Common Location ⑥
Behind the headrest. Open the cover to find the anchor point.
What is Top-Tether?
The Top Tether is an upper tether strap located at the top of a child car seat. It is commonly found on child car seats with a 5-point harness, such as infant car seats or car seats for children under 18 kg. Some models may be designed for children up to 25 kg.
The Top Tether hooks onto the ISOFIX third point in the car to create a three-point installation. This helps reduce movement and keeps the child car seat more stable.
In Taiwan, some people used to call the European-style Top Tether a “Latch” because of the influence of the U.S. LATCH system. To make it easier for local readers to understand, PERO may sometimes use “Latch” to refer to the Top Tether in our articles.
However, “LATCH” does not only mean the Top Tether. It may also refer to the lower anchor connectors, which are similar to the metal ISOFIX connectors used in European-style car seats.
For cars sold in the U.S., the owner’s manual or labels may use terms such as “LATCH,” “anchor,” “LATCH tether anchor,” or “LATCH lower anchor.” These are all related to the concept of a three-point child car seat installation system.
For parents driving U.S.-spec cars, there is no need to worry if you cannot find an ISOFIX label in the car. As long as the car model has passed the required testing and is legally sold in Taiwan, it can be used with an ISOFIX child car seat certified under CNS 11497.
