This classification was established in the USA by the National Lubricating Grease Institute (NLGI). This classifies greases solely in terms of their hardness or softness; no other property of performance level is taken into consideration.

NLGI Consistency

Kinematic Viscosity at 40°C (mm2/s

Minimum

Maximum

000

445

475

00

400

430

0

355

385

1

310

340

2

265

295

3

220

250

4

175

205

5

130

160

6

85

115