<div class="container-flex-wrap">
  <div class="item stretch">stretch 1</div>
  <div class="item stretch">stretch 2</div>
  <div class="item stretch">stretch 3</div>
  <div class="item stretch">stretch 4</div>
</div>
<br>
<div class="container-flex-wrap">
  <div class="item no-stretch">no-stretch 1</div>
  <div class="item no-stretch">no-stretch 2</div>
  <div class="item no-stretch">no-stretch 3</div>
  <div class="item no-stretch">no-stretch 4</div>
</div>
.stretch {
  flex: 1 1 150px;
}
.no-stretch {
  flex: 0 1 150px;
}

.container-flex-wrap {
  display: flex;
  flex-wrap: wrap;
  flex-direction: row;
  /*flex-flow: row wrap;*/
}
.item {
  background-color: lightblue;
  margin: 5px;
  padding: 5px;
}

External CSS

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External JavaScript

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