"We must take sides. Neutrality helps the oppressor, never the victim." - Elie Wiesel
“If you are neutral in situations of injustice, you have chosen the side of the oppressor.” – Archbishop Desmond Tutu
“It is very tempting to take the side of the perpetrator. All the perpetrator asks is that the bystander do nothing. He appeals to the universal desire to see, hear and speak no evil. The victim, on the contrary asks the bystander to share the burden of pain.” - Judith Herman 
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You cannot go wrong with a classic square-style sticker. The clean, crisp edges and simple-but-elegant look make this the most straightforward and popular option.
.: Materials: 100% vinyl with 3M glue backing
.: Glossy finish
.: Four sizes to choose from
.: Grey adhesive left side for white stickers
.: For indoor use
.: Not waterproof