This is a Mil-Spec lower parts kit, minus trigger, trigger guard and grip.

The Builders kit includes the following:

• 1- Standard Safety 
• 1-Safety Detent 
• 1- Safety Detent Spring  
• 1- Standard Bolt Catch  
• 1- Bolt Catch Plunger  
• 1- Bolt Catch Roll Pin  
• 1- Bolt Catch Spring 
• 2- Takedown / Pivot Spring  
• 2- Takedown / Pivot Detent  
• 1- Takedown Pin  
• 1- Pivot Pin 
• 1- Mag Catch  
• 1- Mag Release Button 
• 1- Magazine Catch Spring  
• 1- Buffer Retainer Pin 
• 1- Buffer Retainer Spring