The STABILA 294 Series Type 80T spirit level allows your level size to be as flexible as your job. As you extend the level, the marking point is continuous with no interruptions. A manual locking mechanism tightens the system up when you are ready, just click and go. This system features rubber on the backside of the level to add a non-slip grip to the wall as you work leaving no scratches. The vial gauges are anti-leak, and anti-fog. In normal closed position: your accuracy tolerance will not exceed 1/32in over 72 inches. Extended it will not exceed 1/16in over 72 inches.