(1) Russian consonants /п/, /т/, /к/ etc. are never aspirated no matter what position they have in the word, final, initial or other.
(2) As compared to English consonants in clusters like -pp-, -tt-, -mm- etc. (‘happy’, ‘better’, ‘grammar’), where a double letter produces a single sound, Russian consonants behave differently; I mean both types of consonant clusters: in the middle of the word or at the joint of two words ("...Так как.." or «стаккато» or "завернут то" or «брутто») – we prolong the same sound (unlike English speakers, who pronounce single /t/ in ‘better’ or single /p/ in ‘happy’), actually we articulate double /к/ or double /т/.
(3) As far as "...завернуть то..." is concerned, we have to articulate both /ть/ and /т/; otherwise we couldn’t distinguish between "завернут то" and "...завернуть то..."