src/Metable.php
protected function getMetaBetweenConstraint($column, array $values)
    {
        $min = $values[0];
        $max = $values[1];

        return function ($query) use ($column, $min, $max) {
            $query->where('meta_key', $column)
                ->where('meta_value', '>=', $min)
                ->where('meta_value', '<=', $max);
        };
    }
protected function getMetaBetweenConstraint($column, array $values)
    {
        $min = $values[0];
        $max = $values[1];

        return function ($query) use ($column, $min, $max) {
            $query->where('meta_key', $column)
                ->where('meta_value', '>=', $min)
                ->where('meta_value', '<=', $max);
        };
    }
Query Builder whereBetween override required to pass raw numeric values.

@param  string $column
@param  array  $values
@return \Closure