Enhanced Tactical Multi-Purpose

The Enhanced Tactical Multi-Purpose (ET-MP) hand grenade is a versatile, dual-mode explosive device developed by the United States Army to provide soldiers with selectable fragmentation or concussive blast effects in a single, ambidextrous throwable munition.^[1] Designed for close-quarters combat, it features an electronic fuze that ensures the grenade remains safe until intentionally armed, preventing accidental detonation during handling or transport.^[1] This innovation addresses limitations of legacy grenades by allowing users to switch modes via a simple lever, reducing the logistical burden of carrying multiple grenade types.^[2] Initiated in 2010 following feedback from Army and Marine Corps personnel, the ET-MP project was led by the Armament Research, Development and Engineering Center (ARDEC) at Picatinny Arsenal in New Jersey, with collaboration from the Infantry School and active-duty soldiers.^[1] Development spanned over five years, securing funding in fiscal year 2013, and incorporated advanced safety features including an out-of-line detonation train and millisecond-precision timing in the fuze.^[1] The grenade was developed to replace the M67 fragmentation grenade, in service since 1968, and restore the concussive capability of the discontinued MK3A2 concussion grenade, which was retired in 1975 due to safety concerns.^[1] As the first U.S. Army hand grenade to achieve Fuze Safety Review Board certification and Insensitive Munitions qualification, it was designed to enhance reliability in diverse operational environments.^[1] The ET-MP's design emphasizes user ergonomics and mission flexibility, with a weight and throw range comparable to existing models while prioritizing reduced risk to the thrower.^[3] A transition to the Project Manager for Close Combat Systems was planned for fiscal year 2020; however, as of 2025, the ET-MP has not entered service, with the M67 remaining the standard fragmentation grenade and the M111 adopted in 2021 for offensive blast effects.^[1]^[4]

Overview

Description

The Enhanced Tactical Multi-Purpose (ET-MP) is an American hand grenade developed by the US Army Combat Capabilities Development Command Armaments Center (CCDC-AC) at Picatinny Arsenal, New Jersey.^[1]
This device represents the first new US Army hand grenade design in over 40 years, intended to replace or complement legacy models such as the M67 fragmentation grenade.^[1]
The ET-MP's core innovation lies in its multi-purpose functionality, which enables users to select different effects—such as fragmentation or concussive—within a single grenade body via a simple mechanism.^[1]
Research and development for the ET-MP began in 2010.^[1]

Purpose and Role

The Enhanced Tactical Multi-Purpose (ET-MP) grenade was developed to address a longstanding gap in the U.S. Army's inventory of hand grenades, providing soldiers with a single, versatile device capable of delivering both fragmentation effects for anti-personnel shrapnel dispersion and concussive blast overpressure suitable for confined spaces.^[1] This dual-capability design allows troops to adapt to varying tactical situations without carrying multiple grenade types, thereby reducing overall load and logistical demands in the field.^[5] The ET-MP was intended to serve as a replacement for both the M67 fragmentation grenade—introduced in 1968—and the MK3A2 concussion grenade, which was withdrawn from service in 1975 due to hazardous asbestos content in its exterior coating, leaving the M67 as the sole standard anti-personnel option.^[5]^[6] However, in 2021, the US Army adopted the M111 Offensive Hand Grenade to replace the MK3A2 and restore concussive functionality, while the M67 remains in service as of 2025.^[7] The ET-MP has not entered full production or service. By complementing the M67 while aiming to restore concussive functionality, the ET-MP was designed to enhance close combat effectiveness, particularly in urban or room-clearing operations where blast effects can neutralize threats in enclosed environments without excessive collateral fragmentation.^[1] Key to its strategic rationale is the emphasis on soldier safety and operational reliability, achieved through design improvements that minimize dud rates and reduce risks of accidental detonation during handling or deployment.^[1] These enhancements ensure greater confidence in employment across diverse scenarios, supporting the Army's broader goals for modernized, soldier-centric weaponry in asymmetric warfare.^[5] The grenade's ambidextrous configuration further promotes universal usability among right- and left-handed personnel.^[1]

Development

Background and Initiation

Prior to 2010, U.S. forces primarily relied on the M67 fragmentation hand grenade for offensive operations, which offered only fragmentation effects and required right-handed soldiers to throw with their right hand while left-handed soldiers used their left hand, limiting ambidextrous use.^[1] The MK3A2 concussion grenade, which provided blast overpressure without fragmentation, had been in service but was phased out in 1975 due to its exterior coating containing up to 50% asbestos, posing inhalation hazards to troops.^[1] These limitations left soldiers without a versatile, multi-mode option for varying tactical scenarios, such as enclosed spaces where fragmentation could endanger friendlies or cause excessive collateral damage. Research for the Enhanced Tactical Multi-Purpose (ET-MP) grenade was initiated in 2010 by engineers at Picatinny Arsenal in direct response to feedback from soldiers, who sought safer and more reliable hand grenades capable of addressing diverse combat needs.^[1] This effort stemmed from operational experiences highlighting the shortcomings of existing munitions, with input from Army and Marine Corps personnel proving critical in shaping early design requirements for improved user safety and effectiveness.^[1] The program received programmatic approval and funding through the U.S. Army's Joint Service Small Arms Program (JSSAP), which coordinated joint-service efforts to enhance small arms and munitions technologies, including compliance with insensitive munitions standards to minimize unintended detonations from environmental hazards.^[1] Initial science and technology funding supported the research starting in fiscal year 2013, with a planned transition to full production and fielding targeted for fiscal year 2020.^[1]

Key Milestones and Testing

The development of the Enhanced Tactical Multi-Purpose (ET-MP) grenade was initiated by a warfighter request in 2010, prompting research and prototype efforts at the U.S. Army's Picatinny Arsenal.^[1] From 2010 to 2016, engineers advanced prototype iterations, integrating an electronic fuze system for millisecond-accurate detonation timing and conducting initial safety testing in collaboration with the U.S. Army Infantry School, active-duty Soldiers, and Marines.^[1]^[8] This phase emphasized enhanced reliability through an out-of-line detonation train, which remains inert until the grenade is armed, addressing limitations in legacy designs like the M67.^[1] In September 2016, the U.S. Army publicly announced the ET-MP program, describing it as the first new lethal hand grenade in over 40 years and highlighting its ambidextrous throw mechanism and dual-mode selector switch for fragmentation or concussive effects.^[1] The announcement, led by the Armament Research, Development and Engineering Center (ARDEC), underscored feedback-driven improvements for operational versatility, allowing Soldiers to carry a single grenade type for multiple scenarios.^[1]^[9] Post-2016 efforts focused on maturing the design for acquisition, with a planned transition to the Project Manager Close Combat Systems in fiscal year 2020.^[1] Ongoing testing targeted insensitive munitions (IM) qualification through the Army Fuze Safety Review Board, aiming to make the ET-MP the first lethal grenade featuring an electronic fuze to meet these standards for reduced accidental detonation risks.^[1]^[8] As of 2025, the ET-MP remains in advanced prototyping without confirmed full-rate production or fielding, while the U.S. Army has adopted the separate M111 offensive hand grenade in 2021 to address concussive needs alongside the existing M67 fragmentation grenade.^[10]^[4] This development reflects integration challenges within broader close combat systems modernization.

Design and Features

Fuze and Safety Mechanisms

The ET-MP grenade's fuze system represents a significant advancement in hand grenade technology, featuring a fully electronic design that replaces the mechanical fuses of previous models like the M67. This electronic fuze incorporates an out-of-line detonation train, which remains disengaged during handling and transport to prevent accidental initiation, aligning only after the grenade is thrown and armed through detected acceleration. The system draws on electro-mechanical principles, ensuring arming occurs solely in response to intentional deployment rather than incidental impacts or drops.^[1]^[11] Precise timing is a core innovation of the ET-MP's fuze, enabling detonation delays controlled to within milliseconds for enhanced reliability and mission adaptability. This electronic precision supports integration with the grenade's dual operational modes while maintaining safety protocols. The fuze has undergone rigorous evaluation by the Army Fuze Safety Review Board, marking the ET-MP as the first such qualified system for a U.S. lethal hand grenade.^[1]^[12] Safety is further bolstered by the ET-MP's compliance with Insensitive Munitions standards, making it resistant to unintended detonation from external threats including fire exposure, bullet or fragment impact, and electromagnetic interference. This qualification addresses vulnerabilities in earlier grenades, reducing risks to users and logistics personnel. The design also includes an ambidextrous safety clip and lever assembly, facilitating ergonomic use for both left- and right-handed soldiers without procedural differences.^[1] As of November 2025, the described features are based on the planned design from development efforts initiated in 2010; the ET-MP has not entered production or service, with the U.S. Army continuing to use the M67 fragmentation grenade and having adopted the M111 offensive hand grenade in 2021.^[1]

Modes of Operation

The Enhanced Tactical Multi-Purpose (ET-MP) grenade incorporates a dual-mode selector lever on its body, enabling users to switch between fragmentation and concussive effects with a simple pre-throw flip mechanism for enhanced tactical flexibility.^[2] This design allows a single grenade to perform roles traditionally requiring separate devices, such as the M67 fragmentation grenade and the MK3A2 concussive grenade.^[1] In "Frag" mode, the grenade is intended to produce fragmentation effects comparable to the M67, creating a lethal radius similar to 5 meters for anti-personnel engagements in open areas.^[1] Conversely, "Concussive" mode channels the explosive force into directed blast overpressure without fragmentation, producing a casualty radius of about 2 meters in open spaces, suitable for non-lethal stunning or breaching operations in confined environments like rooms or bunkers.^[13]^[14]^[15] The operational sequence begins with pulling the pin, selecting the desired mode via the lever, and throwing the grenade; the electronic fuze then arms post-throw to mitigate cook-off risks, integrating seamlessly with safety mechanisms for reliable performance.^[1]^[2]

Specifications

Physical Characteristics

The Enhanced Tactical Multi-Purpose (ET-MP) grenade has overall dimensions similar to the M67 grenade for seamless compatibility with standard issue pouches and handling equipment: a diameter of 2.5 inches (64 mm) and a length of 3.5 inches (89 mm).^[16] When filled, the grenade weighs 14 ounces (397 grams), providing an optimal balance of portability for individual soldiers while accommodating sufficient payload for tactical effectiveness.^[1] Its construction consists of a durable steel body encasing 6.5 ounces (185 grams) of Composition B explosive filler, selected for its stability and non-corrosive qualities that support long-term storage without degradation; the body incorporates an ambidextrous ergonomic shape to facilitate a secure, natural grip regardless of the user's dominant hand.^[1] Packaging emphasizes lightweight, individual carry integration into the standard soldier loadout, which minimizes total encumbrance relative to legacy configurations involving multiple specialized grenades.^[17]

Performance Parameters

The Enhanced Tactical Multi-Purpose (ET-MP) grenade contains 6.5 ounces (185 g) of Composition B as its explosive fill.^[18] In fragmentation mode, the ET-MP achieves a primary lethal radius of 5 meters and a casualty radius of 15 meters, with fragments dispersing up to 230 meters and capable of penetrating light cover (as developed in 2016).^[19] The concussive mode generates a 2–3 meter lethal radius from overpressure in open air, extending with greater effectiveness to enclosed spaces to produce stunning effects without shrapnel (as developed in 2016).^[15] An average soldier can throw the ET-MP up to 35 meters, although its design may limit trajectory stability; the electronic fuze contributes to improved reliability (as developed in 2016).^[1]^[19] These specifications are from the developmental phase as of 2016; the grenade has not been publicly confirmed as fielded by 2025. Mode switching enables this versatility between fragmentation and concussive effects via a simple selector.^[1]