3m Wave Form Helix Spring for Wave Motion Demonstration Science Classroom 5 inches with a brass-chrome

5 inches with a brass-chrome water wheel in a 10cm aluminum casing

Hand-painted 4-part human brain model separates into cortical hemispheres and brain-stem regions for lobed-anatomy teaching at introductory biology levels

Four-prong cork-lined retort clamp with an integrated boss head

and inner ear anatomy for upper-level anatomy teaching

injection pump

3m Wave Form Helix Spring for Wave Motion Demonstration Science Classroom 5 inches with a brass-chromeClosing to 3m and extending to 9m, this 20mm diameter steel helix carries longitudinal, transverse, and standing waves visibly enough to compare amplitude, frequency, and S wave vs P wave behavior.