Official Rules

File:Buckler symbol.jpg	Buckler - This weapon has an integral buckler that gives the model a cumulative +1 ARM bonus; for example, a model with two of them gains a bonus of +2 ARM. A model does not gain this bonus while the weapon system with the buckler is crippled or when resolving damage that originates in its back arc.
File:Shield symbol.jpg	Shield - This weapon is a shield that gives the model a cumulative +2 ARM bonus; for example, a model with two of them gains a bonus of +4 ARM. A model does not gain this bonus while the weapon system with the shield is crippled or when resolving damage that originates in its back arc.

Rules Clarifications