12" Connecting Lead with Alligator Clip and 4mm Plug, Black Science at Home_Chemical Science this bottle of coarse 20-mesh

this bottle of coarse 20-mesh iron filings is a staple for classroom magnetism and field-pattern demonstrations

and magnetic strength relationships

Red-coated Alnico cylindrical pair at 50 x 10mm

this 80mm steel needle in a 6mm rod doubles as a precise alignment reference for image-formation and ray-tracing setups

paired with the 750mm black lead to keep wiring color-coded across mid-distance bench setups

12" Connecting Lead with Alligator Clip and 4mm Plug, Black Science at Home_Chemical Science this bottle of coarse 20-meshPlug to clip 12 inch black lead combining a 4mm banana plug at one end with an alligator clip at the other, bridging instrument panels to bare wire components without rewiring.