Generated by SassMeister.com.

no-query-fallbacks-demo.css

.foo {
  background: grey;
}
@media (min-width: 320px) {
  .foo {
    background: blue;
  }
}
.lt-ie9 .foo {
  background: blue;
}
@media (min-width: 769px) {
  .foo {
    background: red;
  }
}
.lt-ie9 .foo {
  background: red;
}

/*Then this max-width implementation is generally **not**
 * what you want to do, but should you need to, you may use
 * the breakpoint mixin with the variable that correlates 
 * with the number only:
 */
.exception-to-the-rule {
  width: 50%;
}
@media (max-width: 444px) {
  .exception-to-the-rule {
    /* applies only to devices less than 444px */
    width: 100%;
  }
}

no-query-fallbacks-demo.sass

// ----
// Sass (v3.3.0.rc.1)
// Compass (v0.13.alpha.10)
// Breakpoint (v2.2.0)
// ----

@import "breakpoint"
$phone-p: 320px
$phone-l: 480px
$tab-p: 444px
$tab-l: 769px
$desk: 960px

/////////////////////////////////////////////////
// No Query Fallbacks  https://github.com/Team-Sass/breakpoint/wiki/No-Query-Fallbacks

$breakpoint-no-query-fallbacks: true

$smartphone-portrait: $phone-p, 'no-query' '.lt-ie9'
$smartphone-landscape: $phone-l, 'no-query' '.lt-ie9'
$tablet-portrait: $tab-p, 'no-query' '.lt-ie9'
$tablet-landscape: $tab-l, 'no-query' '.lt-ie9'
$desktop: $desk, 'no-query' '.lt-ie9'

/////////////////////////////////////////////////

.foo
  background: gray
  +breakpoint($smartphone-portrait)
    background: blue
  +breakpoint($tablet-landscape)
    background: red

/*Then this max-width implementation is generally **not** 
 * what you want to do, but should you need to, you may use
 * the breakpoint mixin with the variable that correlates 
 * with the number only:
 */
.exception-to-the-rule
  width: 50%
  +breakpoint(max-width $tab-p)
    /* applies only to devices less than 444px */
    width: 100%