<div class="progress"></div>

.progress {
  width:80px;
  height:40px;
  border:2px solid #000;
  padding:3px;
  background: 
    repeating-linear-gradient(90deg,#000 0 10px,#0000 0 16px) 
    0/0% no-repeat content-box content-box;
  position: relative;
  animation:p 2s infinite steps(6);
}
.progress::before {
  content:"";
  position: absolute;
  top: 50%;
  left:100%;
  transform: translateY(-50%);
  width:10px;
  height: 10px;
  border: 2px solid #000;
}
@keyframes p {
    100% {background-size:120%}
}