These are usually eye clean stones. They have slight inclusions visible to a trained eye or under magnification. Here is where a dealer would include Type 2 colored gemstones, assuming the dealer is correctly identifying the gemstones and classing them in the correct grade.
Diamonds graded under VS contain minor inclusions ranging from difficult (VS-1) to fairly easy (VS-2) to see under a 10x magnification. There are different types of inclusions possible, but they must be very small in relation to the size of the stone in question. The typical inclusions found in VS grade diamonds are crystals, knots or distinct clouds, some minor surface reaching inclusions such as feathers or cavities. There are also rare cases where a large VS gem contains eye-visible inclusions, as the grading is based on inclusions relative to the size of the gem.