With low be sanded LBlu seals/equivalent to 2RS LLU/LLB (one side: Orange, other side: Black)
Grease does not need to be added extra.
MR18307 Sealed Cartridge Bearing is designed for some DT Swiss, Bontrager, and Giant applications.
This bearing is a peculiar bearing as it's only 1mm different to 6903-2rs which has a 17mm ID, instead of this bearing at 18mm ID. Appears on hubs made by DT Swiss.