What are the small chains behind the turret of the Israeli Merkava tank for?

The chains behind the turret of the Merkava tank are used to protect against RPG-like rockets and armor-breaking shells, which are triggered to detonate in advance, preventing the metal jets from functioning at optimal distances, and thus enhancing the rear hemisphere's defenses. These chains and the U.S. Army in the "Stryker" armored car on the "grid type armor", the principle is basically the same. The advantage is light weight, is considered a major feature of the Israeli Merkava main battle tank.