Replacement Stopper with Secchi Disc for Turbidity Tube Entomology & Zoology_Dissection and S-wave vs P-wave behavior

and S-wave vs P-wave behavior

Universal smartphone desk stand accommodates iPhone

Numbered hand-painted cecum model highlights the ileocecal valve and pouch structure at the junction of small and large intestine for digestive anatomy teaching

the slower-dissolving variant of the fine crystalline form for salt-crystal-growing demos and solubility-rate experiments

Replacement Stopper with Secchi Disc for Turbidity Tube Entomology & Zoology_Dissection and S-wave vs P-wave behaviorPairs a heavy rubber stopper with a 42mm plastic Secchi disc on a threaded post, serving as a drop in replacement for the 2 inch diameter turbidity tube series.