FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K
The official Rare Breed FRT-RD3™ (SEF) — a two-stage, SEF frame, 3-position (Safe / Semi / FRT®) forced reset trigger for the HK MP5 & SP5, 100% made in the USA. Drop-in, duty-grade and backed by our warranty. Buy the original FRT trigger for sale direct from the patent holder.
$615.00
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Description
Rare Breed FRT-RD3™ (SEF) — HK MP5 & SP5 forced reset trigger
Take your HK roller-delayed firearm to the next level with the official Rare Breed FRT-RD3™ (SEF). This drop-in, duty-grade, two-stage 3-position FRT trigger (Safe / Semi / FRT®) fits the HK MP5, MP5K, SP5 and SP5K, and is 100% made and assembled in the USA. Crafted from high-quality materials including 7075 anodized aluminum, it’s the genuine MP5 forced reset trigger for sale from the patent holder — matched to SEF grip frames.
How the forced reset trigger works
In FRT® mode, the FRT-RD3™ (SEF) uses your firearm’s own cycling to drive the trigger forward into its reset position after every shot — so your next round is ready almost as soon as the gun is. The result is a dramatically faster, smoother and more consistent shooting cadence than a standard trigger. Crucially, it stays fully semi-automatic: the trigger fires one round per pull of the trigger, every time, and must fully reset before it can fire again. Want the details? Read what a forced reset trigger is and how a forced reset trigger works, or go deeper on the FRT mechanism.
Innovative design and features
- SEF single-sided safety selector engineered for HK SEF-type grip frames.
- Two-stage, 3-position functionality: Safe, Semi and FRT®.
- Durable 7075 construction for long-lasting performance.
- Drop-in installation in an SEF grip frame — no gunsmithing required.
Specifications
| Platform | HK MP5, MP5K, SP5 & SP5K |
|---|---|
| Grip frame | SEF only |
| Trigger type | Two-stage forced reset trigger |
| Modes | 3-position: Safe / Semi / FRT® |
| Materials | 7075 anodized aluminum & duty-grade components |
| Origin | Designed & assembled in the USA |
What’s in the box
- 1 × FRT-RD3™ trigger
- 1 × SEF single-sided safety selector
- 1 × 1/16″ Allen key
- 1 × 3/32″ Allen key
SEF or AMBI? Choose the right FRT-RD3™
Fit check: this is the SEF version and works only with SEF grip frames. Running an ambidextrous frame? Choose the FRT-RD3™ (AMBI) instead. Building a PTR MP5 clone? See our dedicated SEF selector for the PTR.
Keep it running
Shop genuine FRT-RD3™ parts — SEF selector kits, selector detent kits and more.
Why buy your FRT-RD3™ (SEF) direct from Rare Breed Triggers
When you buy direct, you get the genuine article — not a counterfeit or a grey-market copy. Rare Breed Triggers is the exclusive licensee of the U.S. patents behind forced reset trigger technology, and we pioneered the category with the original FRT-15®. Every FRT-RD3™ (SEF) FRT trigger for sale here is 100% designed, manufactured and assembled in the USA, backed by our limited warranty, and shipped fast from the patent holder. Beware of fakes: if it isn’t from Rare Breed, it isn’t a real FRT®.
Legal & shipping
Forced reset triggers are legal under federal law following Rare Breed’s court victory and 2025 settlement with the United States — see our FRT legal status for the full picture. Some states restrict FRTs, and we do not ship to those jurisdictions; it is your responsibility to know your local laws. Review our FAQs before you order. (General information, not legal advice.)
Buy the FRT-RD3™ (SEF) online
Ready to upgrade? Add the FRT-RD3™ (SEF) to your cart and buy direct from Rare Breed Triggers — the original FRT trigger for sale, in stock and shipping fast. Browse the full HK MP5 & SP5 forced reset triggers or the complete lineup of FRT triggers for sale to find the right trigger for every firearm you own.
