Recently included in its wide range of standard machine elements, ELESA presents different types of level bubbles available as “bull’s-eye levels” for bidirectional measurements or as “screw-on levels” for unidirectional measurements.

The level bubble is based on an elementary principle of physics: partially filling a container with a liquid and leaving an air or gas bubble inside it, this will always be positioned at the highest point of the surface.

The position of the gas bubble in the fluid shows the angle and the direction in which the object is inclined with respect to the horizontal surface.


Bull’s-eye levels for mounting in suitable housings are used to control the horizontal positioning of jigs, machines, devices, equipment and instruments. The range features different materials: anodised aluminium body, natural or black colour with smooth reference surface or with threaded pin (BEL-PM, BEL-BH, BEL-PH), also with fluid housing in polymethylmethacrylate (PMMA) for use also on aerial platforms thanks to the low surface tension and density of the liquid contained within the bubble (BOL-PH). The latter represent a recent extension of the range indicated as NEW products on the website.

In the family, also the series with adjustment pin (BEL-AD) which allows the adjustment of the bubble acting as a pivot point. These are available in anodised aluminium, natural or black colour. By acting on the tightening of the screws, in the three rear threaded holes, it will be possible to get the desired adjustment with respect to the contact surface.

Among the “screw-on levels” series, Elesa offers BEL-MS monodirectional levels with epoxy resin coating, black or grey colour and the new BOL-MB monodirectional levels with polycarbonate (PC) body for fixed or adjustable mounting using steel springs and zinc-plated steel self-tapping screws.The range is completed by BEL-MF level bubbles with mounting flange with anodised aluminium body, natural or black colour, front or rear flange, ideal for scales, tripods and precision instruments and the new BOL-MF level bubble with mounting flange with body in polymethylmethacrylate (PMMA). BOL-MF is equipped with a large lenticular surface which gives it high visibility. The liquid contained within the bubble is characterised by low surface tension and density optimised for use also on aerial platforms.






The transparent housing, in impact-resistant polycarbonate, allows to check the alignment of the bubble in front or side positions.To obtain a bi-directional alignment it is necessary to use two screw-on levels with adjusting screws at 90 degrees.