20m Fiberglass Tape Measure with PVC Cover and Winding Handle Type_Tall Form The wavelength can be changed

The wavelength can be changed with the help of variation in frequency & stress generated using different weights on the one end of rope/thread

Polished non-warping wooden base with a built-in meter-scale carries a compass-box magnetometer

Jumbo three-dimensional frog dissection model with keycard demonstrates amphibian anatomy and organ systems for detailed vertebrate teaching

75-inch metal bell in a plastic shroud

20m Fiberglass Tape Measure with PVC Cover and Winding Handle Type_Tall Form The wavelength can be changedFor field surveys, outdoor physics activities, and long distance laboratory exercises, this twenty meter fiberglass tape measure carries a non conductive waterproof PVC coating.