These devices from Helm Audio are independently great items for enjoying lossless audio but paired together, they take it up a notch. I did enjoy them while I (briefly) used them but seriously- my ears must just be delicate or something. 

They work flawlessly. Everything in the photos is included. I don't recall if more earbud tips originally came with them, but included is only the one pair. They are clean and terribly close to new condition. The metal build of the headphones is super nice.

Will be packed well and shipped with tracking and insurance.

I've included some tech specs from online:

For the Bolt DAC/AMP:

STUDIO GRADE PORTABLE DIGITAL ANALOG CONVERTOR WITH MQA: BOLT delivers studio sound on the go from any mobile device across all listening formats. Supports MQA (Master Quality Authenticated) streaming for unparalleled fidelity in portable audio. Compatible with Android, iOS, Mac, and PC’s. May require extra adapters or third party apps for MQA support.

HIGHEST FIDELITY SOUND: MQA (Master Quality Authenticated) rendering “unfolds” every detail of the original master recording as the artist and engineers intended it to be heard for better-than-CD audio resolutions. Stream MQA content from TIDAL, nugs.net, and Xiami. MQA Certified.

SMARTPHONE, TABLET, MAC & PC COMPATIBLE: USB-C input to a 3.5mm Headphone Output supporting playback of PCM files with sampling rates up to 384 kHz, or DSD files with sampling frequencies up to 5.6MHz. The 3.5mm audio jack seamlessly connects to your wired headphones or speaker system. Note: An adapter is required if you do not have a 3.5mm input jack.

AMPLIFIED AUDIO OUTPUT & HEADPHONE OUTPUT LEVEL MATCHING: Provides an average increase of +6 dB in devices with combined USB-audio output (where a dedicated headphone audio output isn’t available). Headphone output level automatically detects headphone impedance and sets level accordingly (1V for 150 ohms).

THX CERTIFIED AUDIO OUTPUT: Exclusively designed for ultra-low harmonic, crosstalk & crossover distortion. Unlike other mobile MQA-DAC designs, the HELM BOLT physically isolates the DAC from the USB connector for improved EMI isolation, and uses a three oscillator design for superior frequency lock with dramatic improvements over single oscillator DAC designs.

Android 12 Devices: Some Android 12 devices may experience low volume levels using the BOLT. The fix is to upgrade to new firmware found on the HELM Audio Support Page

 

For the F2 Planar Headphones:

•             Made For You: High-End Sound Quality for Everyone Featuring - Planar Magnetic Audiophile-Grade Dual-Driver Speaker Technology for an Audio Lover’s Everyday Use
•             Exclusive Game Changing Sound Quality: Featuring a 6mm Planar Magnetic Driver & a 10mm Dynamic Driver
•             Fit and Function: Designed Small, Portable & Ultra-Lightweight for All Day Comfort and Includes 3 Tip Sizes (S, M, L)
•             Legendary Balanced HiFi Sound with the Planar Magnetic Driver Delivering Perfect Mids & Highs - Then Bring in the BASS with the Custom Dynamic Driver
•             3.5mm Wired Connectivity with In-line Mic & Controls Including Custom Braided Cables Making the F2 a Daily Go To Solution