Clarify the intent of this query

What can you do to improve this query with respect to conveying it's intent for future readers?

SELECT x1.customer_id, x1.rental_date, x1.return_date 
FROM rental x1
JOIN inventory x2
    ON x1.inventory_id = x2.inventory_id
JOIN film x3
    ON x2.film_id = x3.film_id
WHERE x3.length < 90;