Locking caps are attached to the top of well casing and serve the dual functions of preventing surface water

from entering the well through the top of the casing and restricting access by unauthorized persons. The

J-Plugs are manufactured of high strength nylon plastic which is impervious to the effects of water and most

aggressive chemicals for long inexpensive life.

OPERATION: The cap consists of two rigid disks, which are separated by a flexible, squeezable, donut of

hydrocarbon resistant material. The lower portion of the cap is inserted into the well casing and the wing nut on

top is tightened. As the wing nut is tightened the two disks compress the flexible donut.

As it is compressed, the donut expands outward at its circumference, pressing tightly against the inside of the

well casing forming a liquid tight seal. The seal produces enough friction to make it virtually impossible to

remove without loosening the wing nut. A padlock can be attached to prevent the wing nut from being rotated.