The present invention concerns the technological field of the liquid level indication or metering devices using rotational arms or other rotating transmission elements. Problem to be solved: At present, the selective adjustment of the extent of angular rotational movement between the movable body and the static body of a liquid fluid level metering device is done by means of vertical adjustment of the positioning of the extension rod, which changes position both in relation to said movable body and said static body. Problem solving: It is disclosed a liquid fluid level metering device based on angular rotational movement, whose adjustment of the extent of the angular rotational movement between the movable body and the static body occurs by means of the adjustment of the depth of the extension rod in relation to the static body, being unchangeable the alignment and fastening between said extension rod and said movable body.