I want to project a collection applying exporting a value only if a field is inside a range.

Sort of:

```
db.workouts.aggregate({
 $match: { user_id: ObjectId(".....") }
},
{
 $project: { 
        '20': { $cond: [ {$gt: [ "$avg_intensity", 20]} , '$total_volume', 0] }
    }    
 })

```

I need to get the value only if the avg\_intensity is inside a certain range. I will then group and sum on the projection result.

What I am trying to do is applying a $gt and $lt filter but with no much success.

```
db.workouts.aggregate(
{
   $match: { user_id: ObjectId("....") }
},
{
$project: { 
        '20': { $cond: [ [{$gt: [ "$avg_intensity", 20]}, {$lt: [ "$avg_intensity", 25]}] ,    '$total_volume', 0] }
    }    
 })

```

How may I apply both $gt and $lt conditions?