What does Steel Bolts do in AoE3?

Crossbowman: damage bonus against Heavy Infantry +0.75, range (Ranged) +2, range (Ranged (defend)) +2, range (Ranged (stagger)) +2. The game says: "Crossbowmen and Pavisiers gain more range and inflict greater damage to Heavy Infantry and Buildings with their bolts."

Home City card

Steel Bolts

Steel Bolts (tech ID DEHCImprovedCrossbows) is a Home City card in AoE3: Definitive Edition 100.19.18309, in the decks of 1 civilization, sent from the Fortress Age. Effect: Crossbowman: damage bonus against Heavy Infantry +0.75, range (Ranged) +2, range (Ranged (defend)) +2, range (Ranged (stagger)) +2.

Quick answers (3)

Which civilizations have the Steel Bolts card?: Maltese.
What does Steel Bolts do in AoE3?: Crossbowman: damage bonus against Heavy Infantry +0.75, range (Ranged) +2, range (Ranged (defend)) +2, range (Ranged (stagger)) +2. The game says: "Crossbowmen and Pavisiers gain more range and inflict greater damage to Heavy Infantry and Buildings with their bolts."
What is the tech ID of Steel Bolts?: DEHCImprovedCrossbows.

Crossbowmen and Pavisiers gain more range and inflict greater damage to Heavy Infantry and Buildings with their bolts.

What it does

Crossbowman: damage bonus against Heavy Infantry +0.75, range (Ranged) +2, range (Ranged (defend)) +2, range (Ranged (stagger)) +2, line of sight +2

2 further effects (interface, visuals or AI) not listed.

Cost: 1
Sent from: III
Times it can be sent: 1
Game ID: DEHCImprovedCrossbows

In these decks

MalteseIII×1

Source: techtreey.xml and the Home City files, AoE3: DE 100.19.18309 (build 25040513).