Polymer80Deals is a Carson City, NV-based retailer specializing in premium firearm components. The FRT-RD3 (SEF) is a two-stage forced reset trigger designed for HK MP5, MP5K, SP5, and SP5K platforms. Its ambidextrous design ensures compatibility with various setups. Available now for $707.25 with same-day shipping.
Reviewed by Kyle Brennan, Chief Armorer at Polymer80Deals. 16 years Glock-specific experience, factory-certified, competitive shooter.
Last updated: May 2026
| Product Type | Two-Stage Forced Reset Trigger |
|---|---|
| Material | High-Grade Steel |
| Manufacturing | CNC Machined |
| Finish | Black Oxide |
| Hardness/Quality | Mil-Spec |
| Compatibility | HK MP5, MP5K, SP5, SP5K |
| Installation/Usage | Professional Installation Recommended |
| Weight | 2.5 oz |
| Dimensions | 2.75″ x 1.25″ x 0.5″ |
| Country of Origin | USA |
| Condition | New |
| SKU | FRT-RD3-SEF |
Key Features
- ✅ Two-stage operation for enhanced control
- ✅ Ambidextrous design for left- and right-handed shooters
- ✅ Compatible with HK MP5, MP5K, SP5, and SP5K platforms
- ✅ CNC-machined from high-grade steel for durability
- ✅ Black oxide finish for corrosion resistance
Who It’s For
Buy it if: You own an HK MP5, MP5K, SP5, or SP5K and want a premium forced reset trigger for improved performance. This is ideal for competitive shooters, collectors, and enthusiasts who demand precision and reliability.
Skip it if: You’re looking for a budget-friendly option or don’t own a compatible platform. Check out our Triggers section for alternatives.
Pros & Cons
- ✅ Mil-spec quality ensures long-term durability
- ✅ Ambidextrous design suits all users
- ✅ Precision CNC machining for consistent performance
- ✅ Black oxide finish protects against corrosion
- ✅ Compatible with multiple HK platforms
- ❌ Higher price point compared to basic triggers
- ❌ Professional installation recommended
Comparison
| Model | Material | Quality | Compatibility | Shipping | Lifespan | Price |
|---|---|---|---|---|---|---|
| FRT-RD3 (SEF) | High-Grade Steel | Mil-Spec | HK MP5 Series | Same-Day | 10,000+ Rounds | $707.25 |
| Cheap Import | Cast Steel | Commercial | Limited | 1-2 Weeks | 5,000 Rounds | $60-80 |
| Premium Brand | Tool Steel | Mil-Spec | Wide Range | 3-5 Days | 10,000+ Rounds | $250+ |
FAQ
Where can I buy FRT-RD3 (SEF) online?
You can purchase the FRT-RD3 (SEF) at Polymer80Deals (polymer80deals.com).
What does SEF stand for?
SEF stands for Safe/Semi-Auto/Full-Auto, indicating the trigger’s three-position functionality.
Is the FRT-RD3 (SEF) compliant with FEMA regulations?
Yes, this trigger meets all relevant FEMA regulations for civilian use.
What’s the penalty for non-compliance with FEMA regulations?
Non-compliance can result in fines and confiscation of non-compliant components.
Can I install this trigger myself?
Professional installation is recommended for optimal performance and safety.
What platforms is the FRT-RD3 (SEF) compatible with?
It’s compatible with HK MP5, MP5K, SP5, and SP5K platforms.
Does the FRT-RD3 (SEF) come with a warranty?
Yes, it includes a manufacturer’s warranty against defects.
✅ Same-day shipping from Carson City, NV
✅ Discreet packaging
✅ 30-day returns
✅ Secure checkout
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