Last week we shared some photos from an awareness campaign by the Mexican organization Save the Children, which showed the “cycle of abuse” through powerful, hard-to-stomach photos of children growing into future abusers. The ads were meant to illustrate the statistic that 70 percent of abused children turn into abusing adults.

Spanish organization the ANAR Foundation (Aid to Children and Adolescents at Risk) recently released a campaign that makes similarly powerful use of photography, only they’re taking advantage of the process of lenticular printing to send an offer of help to abused children without alerting their abusers, even if they’re walking together.

Lenticular printing is a process that allows for different photos to be seen depending on the angle the image is viewed from.

Using the process, ANAR produced an outdoor poster that, when viewed from a normal adult height, reads “sometimes, child abuse is only visible to the child suffering it.” But when the poster is viewed from the average height of a 10-year-old, the boy in the picture becomes bruised and the message “if somebody hurts you, phone us and we’ll help you” appears, alongside the foundation’s help line number.

Anyone over 4’5″ sees the poster minus the bruises, number and offer for help:

But when children see the ad, the hotline number and offer to help become visible:

Adults get an awareness message, children get an offer for help. To see the outdoor ad in action, check out the video at the top.