Screwless terminal blocks are mainly used where huge volume and fast assembly is required. Ifthe solid wire or stranded with ferrules (connector used to terminate the stranded wire) is used, no tools are needed in order to make the connection. The stranded wire will open the entry and be guarded just by pushing it inside. Some types of terminal blocks have a tool slot or actuator thatenable stranded wires to be used with no ferrules.
The terminal blocks come with spring terminals which mechanicallyclutch inserted wires. When their levers are pressed, they release the wires. Different sizes are available in two alignments (top-entry and side-entry) and two pin spacings (0.2″ and 0.1”).These terminal blocks can be joined to make extended onesor can be eradicated to make them smaller. Each terminal block has two pins and used with PCBs which have the suitabletracks.
There are different types of products available in screwless terminal block category. Have a look-
 Singe feed through: This is a kind of basic terminal block that issuitable for wire-to-wire connections. In this connection, the wire inserted from one side and out the other. These single feed through terminal blocks have one output and one input contact.
 2-Pin, 0.1″ Pitch, Side Entry (3-Pack): The side-entry screwless terminal blocks have anarea of 2.54 mm (0.1″). There are two spring terminals in each blockwhich grip the uncovered ends of inserted wires. This helps in establishing easy and temporary connections to the PCB, in order to make the longer blocks, the units can be joined. They are suitable for 150 V, 2 A (UL) and available in packs of three.
 Disconnect or switch blocks: This kind of terminal block enables the circuit to be easily detached without terminating any wires. A lever type of control is developed to disconnect the circuit. A descending link disconnect uses a joint that can be slipped to the side in order to disconnect the circuit. It uses a removable plug to detach the circuit.
 3-Pin, 0.1″ Pitch, Side Entry (3-Pack):This is another type of side-entry terminal block that has an area of 2.54 mm (0.1″). in this type, each block has 3 spring terminals which automatically hold the bare ends of inserted wires. It helps in developing atemporary connection to the PCB. The units can be combined to build the longer blocks. These terminal blocks are suitable for 150 V, 2 A (UL).
 Fuse holder or fuse block: During the connection, if a short circuit happens, only the part of the circuit linked to this block will get affected. It can be a disconnect block too if dummy fuses are put in instead of normal fuses. A light describes the visual fuse condition and this is called the circuit protection blocks.
 Sensor and actuator block: This type of terminal blocks handles 3-4 photoelectric sensors,3 or 4 wire proximity sensors, or any other kind of 3-4-wire device. It also allows high-density terminations.