I am trying to decifer the various numbers and letters on my grandfather's WW1 army dog tag
CE (I know this refers to his religion Church of England)
5350 (Is this a further regimental number of his service number?)
4 RWS (I'm fairly sure this refers to Royal West Surrey, not sure what the 4 means)
I have a photo of him in his uniform, he had three stripes on his right arm - does this mean he was a sargent?
Many thanks for reading this.