Snap-in-one (SIO)
Petit Lulu's Snap-in-One (SIO) system consists of a SIO insert combined with a cover. The inserts can be clicked into both the Velcro and the press studs of Petit Lulu's one size cover (note: not in the newborn and XL cover).
A SIO Complete consists of a SIO Basic Start inlay and a cover. A SIO Complete is cheaper than a separate SIO insert and cover.
The covers can be aired after a change so that they can be reused. As a result, you need fewer covers than inserts.