Wingbarless leaf warbler

Leaf warblers are warblers of the genus phylloscopus, of the family Phylloscopidae.
Most leaf warblers have wingbars and what is that leaf warbler in Vietnam without wingbar?

1/ Tickell's leaf warbler (Phylloscopus affinis)

2/ Radde's warbler (Phylloscopus schwarzi)

3/ Yellow-streaked Warbler
Phylloscopus armandii

4/ Dusky warbler (Phylloscopus fuscatus) 

5/ Buff-throated Warbler
Phylloscopus subaffinis

6/ Gray-hooded Warbler
Phylloscopus xanthoschistos