Serratura Euro Cilindro Pollice UPVC Serratura a Barile Porta in Legno Chiavi Extra Tagliabili
"T" refers to the Thumb-turn side (or the inside of the lock). For example, 45T55 refers to 100mm Cylinder with the thumbturn being in 45mm side of the cylinder. The Thumb Turn needs to be in the inside of the door.