90° FLAT ELBOW is a fitting used in piping systems that allows pipes to make a 90-degree turn in a plane. This type of elbow is very common in HVAC (heating, ventilation and air conditioning) systems to change the direction of airflow. The following is a product introduction to this 90-degree flat elbow:

Material:
Usually made of durable plastic or metal, such as PVC, ABS plastic or galvanized steel, which is corrosion-resistant and abrasion-resistant.
Design:
The design is simple and easy to install and maintain.
Open at both ends, convenient for connecting pipes of different diameters.
Size:
A variety of sizes are available to meet the connection needs of pipes of different diameters.
According to the table you provided, there are three models: FE-WP75, FE-WP100 and FE-WP130, and the length (L), width (W) and height (H) of each model are as follows:
FE-WP75: length 128mm, width 80mm, height 70mm.
FE-WP100: Length 142mm, width 109mm, height 72mm.
FE-WP130: Length 170mm, width 140mm, height 98mm.

Application:
Used to connect straight or flexible ducts, especially where the direction of the duct needs to be changed.
Suitable for ventilation systems, heating systems, air conditioning systems, etc.
Installation:
Easy to install, usually connecting the pipes by insertion or snap-on.
Sealant or sealing gasket may be required to ensure the tightness of the connection to prevent air leakage.
Maintenance:
Regularly check the sealing and structural integrity of the elbow to ensure the reliability and safety of the system.
Product advantages:
Flexibility: Able to adapt to the connection needs of pipes of different diameters and shapes.
Durability: Made of high-quality materials, with good corrosion resistance and wear resistance.
Easy to install and maintain: Compact design, easy installation, easy maintenance and replacement.