SOLVED: answer posted below

How can I get values from this pivot and specifications table?

I want to display this in a template like:

-Model (name from specifications table)

--Brand (attribute form pivot table): example1 (value from pivot table)

--Model (attribute form pivot table): example123 (value from pivot table) ...

In ProductController I tried returning something like this $product = Product::with('specifications')->first();, but then I can get only data from specifications table and if I try $product = Product::with('product_specification')->first(); I get error Call to undefined relationship [product_specification] on model [App\Product].

Pivot table:

public function up()
{
    Schema::create('product_specification', function (Blueprint $table) {
        $table->engine = 'InnoDB';

        $table->increments('id');
        $table->integer('product_id')->unsigned()->index();
        $table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
        $table->integer('specification_id')->unsigned()->index();
        $table->foreign('specification_id')->references('id')->on('specifications')->onDelete('cascade');
        $table->string('attribute');
        $table->string('value');
    });
}

Specifications table:

public function up()
{
    Schema::create('specifications', function (Blueprint $table) {
        $table->engine = 'InnoDB';

        $table->increments('id');
        $table->string('name')->unique();
        $table->timestamps();
    });
}

Product model:

public function specifications() 
{
    return $this->belongsToMany(Specification::class, 'product_specification');
}