regular maintenance masks like hydrating, refreshing, cooling
can do once every 3 or 4 days.......but some ppl oni do once a
week.......depends on skin condition
treatment masks like brightening, deep cleansing, pore refining,
skin renewal once every 3 maintenance sessions
means 
maint - maint - maint - treatment - maint -
maint - maint - treatment
SKII masks buy from SKII counters lah
10pcs for $170
