This Aluminum I-Beam Spirit Level Features Three Vials: A 180 Vial And Two 90 Vials. It Has Easy-To-Read Graduation Marks On The Top Side Starting From Zero Cm In The Middle And Extending Both Left And Right. The Vials Are Uv And Shock-Resistant While The Rubber End Caps Provide Added Protection If The Level Is Dropped. There Are Hang Holes At Both Ends For Easy Storage. The Accuracy Is 0.5Mm In A Standard Working Position.