Products and Services Overview

The average utility spends $30-$40 per year per valve box to clean out accumulated dirt, debris and insects and faces continuing operational inefficiencies due to valves that cannot be operated in emergency situations. Terrorism and vandalism pose ongoing threats. And liability claims for damages due to valves that cannot be operated in emergencies or displaced lids continue to multiply.

AMPro's new Locking Lids are the simple and most affordable solution available! They have evolved from designs that have been tested over the last twelve years in hundreds of major utility systems.

AMPro products are designed with utility managers and crews in mind. Managers are assured that all valves are accessible. Crews have sealing lids that are simple to install and remove and work effectively. Trained and experienced crews can be employed in exercising critical valves rather than cleaning valve boxes! Utilities using AMPro products estimate a payback of 8 to 17 months. And all AMPro products carry a ten-year replacement warranty!

AMPro Locking Lids are available in various sizes and can include locator coils, ID tags and custom embossing. Keylock models are also available to comply with OSHA Lockout/Tag standards.


AMPro® utility valve box lids consist of a circular disc with an integrally connected cylinder of slightly smaller outer diameter projecting from the lower side, and of sufficient extension to produce an overall lid height to match the corresponding valve box lid retention feature. Around the perimeter of the cylinder and in close proximity to the top disc is an elastomeric seal designed to span the gap between the lid and the valve box, thereby preventing the passage of dirt, debris and insects. In the center of the lid's top is a conventional pentagon nut attached to a course pitch, left-hand threaded bolt that projects downward from the lid top. Threaded onto this bolt is a follower block that is connected to three sets of pivotal arms that extend radially outward toward the lid perimeter.

Locking is accomplished when the lid is positioned onto a valve box lid seat and the pentagon nut is rotated clockwise. This action causes the follower block to descend, causing the pivotal arms to rotate and the outer extension of the arms to rise until contacting the underside of the valve box lid seat ring. Upon contact, the lid is locked in place.

Unlocking is accomplished by rotating the pentagon nut in a counter-clockwise direction until the first resistance is encountered. At this point, the pivotal arms have been retracted sufficiently to allow removal of the lid from the valve box.

The optional ID disc contains blanks to enter user information such as the type of valve, utility, opening direction, direction of flow, number of turns, etc. The top surface of the lid itself contains two recessed slots at opposite sides of the perimeter to be used as pry slots for lid removal.

Materials used in construction include:

Body: Molded of commercial grade Polycarbonate/ABS alloy, with an izod-impact value of 10-12 ft.lbs./in. when tested in accordance with ASTM-D-256. Carbon black is added for color and UV resistance.

Seals: Molded of Kraton-G elastomer, with an ultimate tensile strength of 450 to 600 PSI when tested in accordance with ASTM D624, Die C. Carbon black is added for color and UV resistance. Locking Mechanism: Molded of the same Polycarbonate/ABS alloy as the body.

Metal Hardware: Commercially available stainless steel.

Celebrating 56 Years Serving the Gas and Water Industries