Retainer assembly including a tissue thickness compensator

An implantable layer for use with a surgical stapler, the implantable layer comprising:

• a first layer comprising a first side, wherein the first side comprises an opening;
• a second layer comprising a second side, wherein the second side extends at least partially through the opening to hold the second layer relative to the first layer, and wherein a pocket is defined between the first layer and the second layer;
• and
• a bioabsorbable material in the pocket.

A surgical stapling system, comprising:

• an end effector comprising a jaw;
• and
• an implantable layer attachable to the jaw, wherein the implantable layer comprises:
• a first layer comprising a first side, wherein the first side comprises an opening;
• a second layer comprising a second side, wherein the second side extends at least partially through the opening to hold the second layer relative to the first layer, and wherein a pocket is defined between the first layer and the second layer;
• and
• a bioabsorbable material in the pocket.

An implantable layer attachable to a jaw of a surgical stapling device, the implantable layer comprising:

• a first layer comprising a first side, wherein the first side comprises an opening;
• a second layer comprising a second side;
• and
• a connection interface, wherein the second side extends at least partially through the opening at the connection interface to hold the second layer relative to the first layer, and wherein a pocket is defined between the first layer and the second layer.