S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)

Q: What is the product code of K253406?

The FDA product code is LHN – System, Radiation Therapy, Charged-Particle, Medical, a Class II (moderate risk) device regulated under 21 CFR 892.5050.

FDA 510(k) K253406 · Mevion Medical Systems, Inc.

Substantially Equivalent

510(k) numberK253406

Submission

Device name: S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)
Applicant: Mevion Medical Systems, Inc.
Littleton, MA, US
Received: September 30, 2025
Decision date: March 25, 2026
Decision: Substantially Equivalent (SESE)
Type: Traditional 510(k)
Summary: 510(k) summary available from FDA

Official FDA 510(k) record

Device classification

Product code: LHN – System, Radiation Therapy, Charged-Particle, Medical
Device class: Class II (moderate risk)
Regulation: 21 CFR 892.5050
Specialty: Radiology

Other 510(k)s with product code LHN

510(k)	Device	Applicant	Decision
K260174	Probeat-CrLHN · Traditional	Hitachi High-Tech Corp.	06/11/2026SE
K252815	ProBeam 360 Proton Therapy System v3.0LHN · Traditional	Varian Medical Systems, Inc.	04/23/2026SE
K250986	S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)LHN · Traditional	Mevion Medical Systems, Inc.	09/12/2025SE
K243900	eMotus Respiratory Motion Management SystemLHN · Traditional	Empnia, Inc.	06/27/2025SE
K242418	P-Cure Proton Therapy System (PPTS)LHN · Traditional	P-Cure, Ltd.	05/12/2025SE
K232032	Probeat-FrLHN · Traditional	Hitachi, Ltd. Radiation Oncology Systems…	01/12/2024SE
K231863	ProBeam 360° Proton Therapy System v2.0 (Multiroom)LHN · Traditional	Varian Medical Systems, Inc.	10/06/2023SE
K221996	P-Cure Proton Beam Therapy SystemLHN · Traditional	P-Cure, Ltd.	03/20/2023SE
K220883	Small Field ApplicatorLHN · Traditional	Hitachi, Ltd. Radiation Oncology Systems…	12/15/2022SE
K221791	ProBeam 360° Proton Therapy SystemLHN · Traditional	Varian Medical Systems, Inc.	12/01/2022SE

More from Varian Medical Systems, Inc.

510(k)	Device	Decision
K250986	S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)LHN · Traditional	09/12/2025SE
K172848	MEVION S250i Proton Beam Radiation Therapy DeviceLHN · Traditional	12/27/2017SE
K120676	S-250 Proton Beam Radiation Therapy SystemLHN · Traditional	06/04/2012SE

Questions and answers

When was S250-FIT Proton Beam Radiation Therapy Device (S250-FIT) cleared by the FDA?

S250-FIT Proton Beam Radiation Therapy Device (S250-FIT) (K253406) received a 510(k) decision of Substantially Equivalent on March 25, 2026, 176 days after the submission was received.

What is the product code of K253406?

The FDA product code is LHN – System, Radiation Therapy, Charged-Particle, Medical, a Class II (moderate risk) device regulated under 21 CFR 892.5050.