The BS3A has a type A pinned stationary seat, pressure balanced, manufactured in accordance with UNI EN 12756 (ex DIN 24960). Suitable for clockwise or anti-clockwise rotation.

With the three drive lugs on the rotating body, the mechanical seal can tolerate high levels of vibration and mechanical stress.

The O-ring is easily romovable and refitted when assembling the seal on shaft with keyways, threads or sharp edges. the BS3A version is supplied with a single spring and is more suitable for moderately dirty liquids.