Learn Finnish: Onko tämä moduuli kestävämpi kuin tuo toinen komponentti? - Is this module more durable than that other component?

First, the verb kestää (to endure or last) is turned into the present active participle kestävä (enduring or durable). Because participles often function exactly like adjectives, they can be graded into comparatives and superlatives. You form the comparative here by simply adding the standard -mpi suffix to the word's stem, giving you kestävämpi.

Could I express "than that other component" without using the word kuin?

Yes! Instead of using kuin followed by the nominative case (tuo toinen komponentti), you can drop kuin and put the compared phrase into the partitive case. The alternative would be tuota toista komponenttia kestävämpi. Both structures are completely natural, though using kuin is often easier to parse when the compared phrase is long.

The word toinen can mean either "second" or "other". How do I know which one it is here?

Context is key, but the demonstrative pronoun tuo (that) is your biggest clue here. When toinen is paired with pointing words like tuo or tämä (this), it almost always translates to "other" rather than "second".

If I wanted to emphasize that it is this module being compared, how would the sentence change?