The Stanley FatMax 1-43-556 is a 120cm I-beam magnetic spirit level with three vials and an accuracy of 0.5mm/m. The I-beam profile is lighter than the equivalent box-beam design, making it easier to handle overhead and at height. At 1.042kg compared to the 1.159kg box-beam 120cm, the weight difference is noticeable over a full day of repeated lifting and positioning.

The aluminium I-beam construction provides good rigidity for its weight, though the box-beam variant is the stronger option for heavy site abuse. The I-beam is the better choice for second fix, finishing work, kitchen fitting, and applications where the level is handled frequently and precision matters more than outright durability. Rare earth magnets in the base hold the level to steel surfaces, freeing both hands for marking and adjustment.

Three solid block acrylic vials cover horizontal, vertical, and 45-degree measurements, all magnified for improved readability. The vials are bonded into the frame and maintain their accuracy through normal site conditions. Bi-material hand grips at both ends provide a secure hold for positioning, and shock-absorbing end caps protect the level from drops.

Key Specifications: Length: 120cm. Profile: I-beam. Vials: 3 (horizontal, vertical, 45 degree). Accuracy: 0.5mm/m. Magnets: Rare earth. Construction: Aluminium I-beam. Model: 1-43-556. Weight: 1.042kg. Dimensions: 1220 x 30 x 70mm.