It is used for centering casing and tubing columns and preventing damage to equipment during their descent into the well.
| Nominal pipe diameter, in | 4,02 | 4,49 | 5,51 | 6,61 | 7,01 | 9,65 |
| Outer diameter at the blades, in | 4,80…5,39 | 5,12…5,59 | 6,22…7,13 | 7,36…8,43 | 7,68…8,43 | 10,43…11,69 |
| Length, max, in | 7,87 | 7,87 | 11,81 | 11,81 | 11,81 | 11,81 |
| Inner diameter (+0,08), in | 4,09 | 4,57 | 5,63 | 6,73 | 7,13 | 9,76 |
| Body diameter (±0,04), in | 4,57 | 4,92 | 6,02 | 7,17 | 7,48 | 10,2 |
| Blade width, in | 1,18 | 1,18 | 1,57 | 1,57 | 1,57 | 1,97 |
| Screw hole size | М10 | М10 | М16 | М16 | М16 | М16 |
