Projection Screen 36 x 48" LabLearner Adjustable mass on one fork

Adjustable mass on one fork shifts its 440Hz pitch by a few hertz

sized for individual student-lab use in simple-machines units

the polished 90-45-45-degree faces redirecting light at right angles for total internal reflection demos

Designed to electrolyze water into separately collected hydrogen and oxygen

Projection Screen 36 x 48" LabLearner Adjustable mass on one forkWall automatic roll back spring action screens (box type casing), with hooks for mounting on walls and an AUTOMATIC roller mechanism for winding. Wall automatic roll back spring action screens (box type casing), with hooks for mounting on walls and an AUTOMATIC roller mechanism for winding. Size : 36 x 48"