DIFF Subgroup
E21B 33/136 Baskets, e.g. of umbrella type
Introduced: September 1968
Full Title
Sealing or packing boreholes or wells > in the borehole > Methods or devices for cementing, for plugging holes, crevices or the like > Baskets, e.g. of umbrella type
No child classifications to compare. This is a leaf node in both IPC and CPC.