Closed keyholes
Lifting keyholes encapsulated to reduce the ingress of sand/silt etc. and the escape of odours.

Clear opening
The nominal unobstructed access opening of the frame, neglecting minor intrusions such as the corner fillets of some rectangular frames.

Corner triangles
Locking bosses located in the corners of the unit to allow a tile inlay to be fitted efficiently.

Corrosion resistant locking bolts/screws
Standard stainless steel/brass locking bolts/screws.

Cover peep-in
This facility can be provided where applicable to a unit where regular below ground equipment observation is required.

Double seal
Double resistance seal to deter the ingress of surface water and the escape of odours at atmospheric pressure.

Decorative trim/edges
Cover and frame edging available in brass/stainless steel to improve, where necessary, the aesthetic appearance of the unit when installed.

Galvanising
Sacrificial protective hot dip zinc coating in accordance with BS EN ISO 1461.

GRP plate
Glass reinforced plastic plate usually located under a cover to provide additional protection against the ingress of sand/silt etc. or the escape of odours at atmospheric pressure.

Lokanlift
Easy to operate turn buckle locking system, key provided.

Plain seated
Non-sealed, butt jointed contact between a cover and frame.

Recessed cover
Cover recessed to allow the insertion of chosen material usually to match the surrounding area.

Safety grid
A fabricated steel grid housed under a cover when installed to protect underground assets or offer fall protection.

Sealing gasket
Rubber seal located between the cover and frame. An alternative to the single/double seal traditional grease method.

Securing bolts
Provision is made in the frame of certain units for the insertion of bolts for positive fixing to the chamber (bolts not supplied).

Single seal
Single resistance seal to deter the ingress of surface water and the escape of odours at atmospheric pressure.

Slide-out
Cover removable by sliding action rather than vertical lift.

Torsion spring
Fitted to the unit to assist in the opening/closing of the cover.