A high-precision bubble level in a machined aluminum housing — the first tool to reach for when setting up a turntable. Everything else in turntable setup assumes the platter is level. Anti-skate behaves differently on a tilted deck, tracking force reads inconsistently, and the stylus sits in the groove at an angle it was never meant to. The AT615a is a bull's-eye bubble level machined from solid aluminum, so it is rigid, non-magnetic and will not mark the platter. Set it on the stationary platter, read the bubble against the ring, and adjust the feet or the shelf until it centers. Worth checking at two or three points around the platter, and again with the dust cover in its normal position. Features High-precision bubble level made specifically for turntable setup Machined solid aluminum housing — rigid, non-magnetic and won't mark the platter Circular bull's-eye reading shows level in both axes at once Compact 37 mm puck sits stably on any platter or plinth The correct first step before setting tracking force, VTA and anti-skate Specifications Type: Bull's-eye bubble (spirit) level Dimensions: 37 mm (1.5″) diameter x 17 mm (0.7″) high Material: Machined solid aluminum with high-precision bubble insert Use: Place on the stationary platter, center the bubble by adjusting the turntable's feet or its shelf, then re-check at several points around the platter