Abstract: The retractable test probe includes a main sleeve, a needle and a rotation positioning mechanism. The needle is rooted in the main sleeve. The rotation positioning mechanism includes an eccentric incoaxially fastened to the needle and a flexible sleeve around the eccentric and in the main sleeve. When the needle is turned towards a specific direction, the eccentric will be firmly fastened in the main sleeve through the flexible sleeve, when the needle is turned reversely, the eccentric will be released from the flexible sleeve to be retractably movable.

Abstract: A probing rod includes a main casing and a rotating mobile probe, and the rotating mobile probe includes a conductive tube, a needle and a rotating mobile structure, and the conductive tube is contained in the main casing; the rotating mobile structure includes an outer thread formed on the needle and an inner thread formed on the conductive tube, and the outer thread and the inner thread are screwed with each other, such that the needle can perform a linear movement with respect to the conductive tube. Therefore, the needle can be moved with respect to the main casing to achieve the effect of adjusting the length of the probe that extends out from the main casing.

Abstract: The retractable test probe includes a main sleeve, a needle and a rotation positioning mechanism. The needle is rooted in the main sleeve. The rotation positioning mechanism includes an eccentric incoaxially fastened to the needle and a flexible sleeve around the eccentric and in the main sleeve. When the needle is turned towards a specific direction, the eccentric will be firmly fastened in the main sleeve through the flexible sleeve, when the needle is turned reversely, the eccentric will be released from the flexible sleeve to be retractably movable.

Abstract: The electric meter contains a number of indicator units radially arranged along the circumference of a selection dial and a backlight switch. Each indicator unit contains a lighting element marked with a label. The backlight switch, when engaged, turns on the lighting element of the indicator unit pointed by the selection dial so that its label is visible in the dark and the operation mode of the electric meter is identifiable, even though there is no or little illumination.

Abstract: The hook meter contains a body member, a static arm, a moveable arm, both extended from a top end of the body member. The static and moveable arms are shaped so that each has a side surface rests against each other, thereby forming a closed area. On a spot of the static arm where it is not covered by the moveable arm, a light generation element is provided. As such, the light generation element's light is not blocked by the static and moveable arms, whether they are closed together or separated apart. The hook meter therefore could be conveniently operated in a dark or dimly lit environment.

Abstract: The test probe with illumination for working with various electrical test and measurement devices contains a light generation member to project light in front of a test pin of the test probe so that the test probe could be conveniently operated in the dark. According to the present invention, the light generation member is housed in a chamber of the test probe's body member. The light generation member contains a light generation circuit and a battery pack. The light generation circuit has a light generation element and a switch element with a control means exposed outside the body member. By engaging the control means, the light generation element is turned on and off.

Abstract: A clamp meter is provided for measuring consumption of current and power of an electrical appliance. The clamp meter includes a power inlet port and a power outlet port that are in controlled connection with each other. A current detection element is arranged between the power inlet port and the power outlet port. When the power inlet port is connected to a power source and the power outlet port is connected to an electrical appliance to be detected, with the electrical appliance turned on, the current detection element detects and converts the current flowing through the power outlet port into a digital signal, which is displayed on a display device mounted on the clamp meter, whereby, through the data and information displayed on the display device, a user may get aware of the power consumption of the electrical appliance and abnormality of power consumption thereof.

Abstract: The clamp meter contains a revolving member configured between the meter's body member and jaw member. The revolving member is composed of a first base and a second base located on the interfacing sides of the body member and the jaw member, respectively. The first base and the second base are revolvably joined together by an axle extended axially from the body member into the jaw member via the first and second bases' aligned axle holes. The first base has at least a roller ball elastically embedded in a concave and exposed towards the second base. The roller ball would roll into one of a number of notches of the second base as the base and jaw members are rotated relative to each other, thereby creating a number of preset configurations of the included angle between the body and jaw members.

Abstract: The clamp meter contains a revolving member configured between the meter's body member and jaw member. The revolving member is composed of a first base and a second base located on the interfacing sides of the body member and the jaw member, respectively. The first base and the second base are revolvably joined together by an axle extended axially from the body member into the jaw member via the first and second bases' aligned axle holes. The first base has at least a roller ball elastically embedded in a concave and exposed towards the second base. The roller ball would roll into one of a number of notches of the second base as the base and jaw members are rotated relative to each other, thereby creating a number of preset configurations of the included angle between the body and jaw members.