An apparatus for adjusting the height and inclination of roadway and greenway appurtenances includes a rigid annular support ring mountable onto a rigid annular spacer ring sized so as to be mountable onto a manhole and a manhole frame mountable onto the support ring. The manhole frame is substantially...http://www.google.fr/patents/US6997639?utm_source=gb-gplus-shareBrevet US6997639 - Method and apparatus for adjusting the height and inclination of roadway and greenway appurtenances
Method and apparatus for adjusting the height and inclination of roadway and ...
