The Silverback Desert Tech SRS spring guide is a first-party original upgrade part designed to offer increased performance for your stock SRS A1 / A2.  The guide also includes a thrust bearing for better shooting consistency. 

Compatibility: 

• Silverback Desert Tech SRS A1 
• Silverback Desert Tech SRS A2 

Includes: 

• x1 Silverback SRS Nylon Spring Guide w/ Thrust Bearing (for Pull Bolt)