Blue Epoxy Wire Test Tube Rack, 40-Hole (4 x 10), for 20-22mm Tubes Material_Nylon the candy-bar form letting students

the candy-bar form letting students break each piece into smaller magnets that retain their own north and south poles

forming a half-meter square for ecological field sampling and population-count fieldwork

exposing the moving parts so students see directly how a DC current drives a rotating magnetic field

and vascular bundles for plant anatomy and photosynthesis teaching

inner diameter measures 9mm

Blue Epoxy Wire Test Tube Rack, 40-Hole (4 x 10), for 20-22mm Tubes Material_Nylon the candy-bar form letting studentsBlue epoxy coated steel wire test tube rack with 40 holes in a 4 by 10 layout, sized for 20 to 22 mm tubes and resistant to lab reagent splashes on classroom benches.