FRAME 

It is round-shaped, with a circular net opening. It presents a rectified supporting surface of the cover, it has a continuous EPDM gasket as single ring (o-ring), to increase stability and eliminate any rocking or noise. The MUS model presents a special provision to host the GRP sealing plate, which creates a water-tight .Outside, the external border is flanged to optimize its hold in the cement and the insertion of anchoring bolts. 

COVER 

It is round-shaped, hinged to the frame with maximum opening of 110°, 90° is the safety position (automatic locking) with the possibility to remove the same cover without disassembling the hinge. The stability is guaranteed from the turning process and from the selfcentering guides. The closing system with key is made of stainless steel and it is placed outside the cover; it can be handled with a special key, which guarantees safety and prevents the opening of the cover by non authorized personnel. Furthermore, the key becomes a comfortable handle for opening and closing the cover. The MUS model obtains the covers` blocking through three stainless steel screws, which create a water tight system. The upper surface is designed to be non-skid to allow the complete flow of water and avoid the creation of ice. 

GRP SEALING PLATE 

The GRP sealing plate is realized in reinforced glass and has a thickness of 7 mm. It has the form of a plug with a flange, to prevent the plate dropping through the access opening. It gets located inside the frame without causing any reduction to the dimensions of the specified openings. The GRP is gas tight from both sides and its seal material is EPDM.The lifting and the fixing of the plate is obtained through two securely laminated GRP lifting handles.