Abstract: A vial for a builder's level includes a body with an interior wall and a body cavity containing a bubble. A marker ring is exposed in the cavity. In the improvement, the ring is embedded in the body and the interior wall and the ring have surfaces machined and coextensive with one another. The bubble moves smoothly across the machined wall and ring surfaces. A new method for making a level vial includes providing an intermediate vial product with a body wall having at least one marker ring embedded in it and machining the wall and the ring to form a wall surface free of discontinuities. The intermediate vial product is also disclosed.

Abstract: A level instrument for determining angular relationships includes a frame having a rail section defining a working surface, a vial, and an end plate affixed to the frame. The end plate has a plastic body with integral lip, shoulder and stake or pawl elements. The frame includes passages which receive the stake or pawl elements to permanently interconnect the end plate and frame. Indexing elements automatically orient a shoulder and an edge of the end plate adjacent to the rail section defining the working surface to prevent false level readings occasioned by displacement. A method for constructing the level of the invention which includes affixing the end plate to the frame, displacing a portion of the lip overlaying the frame passage into the passage, to permanently anchor the end plate to the frame.