If you want a flexible open-ear headset with a charging dock and up to 24 hours of combined playtime for jogging, choose Monster Open Ear AC360; if you need bone-conduction audio with built-in MP3 storage and deeper waterproofing, choose HAKII Sole Bone Conduction.
The Monster is the simpler fit for outdoor runs where you want Bluetooth listening and a longer total battery allowance. HAKII makes more sense if your route includes swimming, or you want music available without your phone. Neither isolates your ears, but their designs and day-to-day strengths are different.
• Monster Open Ear AC360: Its open-ear design, up to 8 hours of playtime per use, and up to 24 hours with the charging dock suit longer stretches away from a charger. Its trade-off is that it has no MP3 mode or stated built-in storage.
• HAKII Sole Bone Conduction: Bone conduction, Bluetooth/MP3 dual mode, and IP68 waterproofing make it the more versatile choice for swimming and phone-free listening. Its stated battery life is up to 10 hours per charge, without the longer dock-assisted total listed for Monster.
• For jogging: Choose Monster if you want the charging dock to extend the overall listening allowance; choose HAKII if you prioritize a secure sport fit, phone-free music, or swimming use.
• Who each pick is for: Monster suits runners who want a straightforward open-ear Bluetooth setup; HAKII suits active listeners who want built-in storage and more extensive water protection.
Monster AC360 is an open-ear Bluetooth headset built around a lightweight fit, touch controls, and a charging dock. Its listed Bluetooth version is 6.0, and its connection range is up to 10 meters. That gives you a useful bit of freedom from a paired device, though it still relies on that device for Bluetooth music and calls. There is no headphone jack, so wired listening is not part of the design.
The battery figures are worth reading as two separate things: Monster lists up to 8 hours of use at a time and up to 24 hours with the charging dock. For a jog followed by errands or another workout later, the dock-assisted total may be more useful than a single-session figure alone. The dock is also the key part of the battery story; the listed 24 hours should not be read as continuous playback from one charge of the headset.
The headset has an IPX5 rating, which is intended to help guard against rain and sweat. That is relevant for outdoor jogging and gym sessions, but it is not the same as HAKII’s IP68 rating for submersion. Monster also lists DNN noise filtering for calls, a 16 mm dynamic driver, and a wireless rotary design with a lanyard. The lanyard adds a carry option when the headset is not in use, while touch control keeps playback adjustments on the device.
How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-10-22 · 8 min read · Independent comparison
Who should skip it: Skip Monster if you need built-in MP3 playback or headphones rated for submersion.
HAKII Sole uses bone-conduction audio and an open-ear design, leaving the ear canals uncovered. The stated benefit for a runner is awareness of surrounding sounds while listening, rather than an enclosed fit that blocks the ears. Its Bluetooth range is listed as up to 15 meters, compared with Monster’s 10 meters, and the controls are physical push buttons rather than touch controls. That may appeal if you prefer pressing a button instead of tapping a surface while moving.
The standout practical feature is dual Bluetooth/MP3 mode. HAKII lists built-in storage at 16GB in its feature details, while its product title states 32GB. Because those figures conflict, I would not assume a specific capacity without checking the product information before buying. The core point is that HAKII is presented as having onboard music storage, so it can offer a phone-free listening option. That can be useful on a run when you do not want to carry a phone, or around water where Bluetooth use may not be practical.
HAKII lists IP68 waterproofing, a 27 g weight, and up to 10 hours of playback on a single charge. IP68 is the stronger water-protection claim here and is the reason this model is the clear choice of the two for swimming. Its fit uses a silicone earhook, and the product information describes the design as secure for workouts. The trade-off is that its battery figure is up to 10 hours per charge, while Monster lists up to 24 hours when using its charging dock. HAKII’s 10-hour figure is the more straightforward single-charge measure, but it does not give the same dock-assisted total.
I would look closely at HAKII if your routine moves between jogging, gym sessions, and swimming, or if you want the option to leave your phone behind. It also makes a strong case for someone who likes physical buttons and an explicitly lightweight design. Its stated Bluetooth and MP3 modes add flexibility, but the listed storage-capacity discrepancy is worth resolving before you choose.
Who should skip it: Skip HAKII if you want Monster’s dock-assisted 24-hour total or prefer touch controls.
Side-by-Side: Which Should You Choose?
• Longer stated total with a charging dock → Monster Open Ear AC360. Monster lists up to 8 hours per use and up to 24 hours with its dock. HAKII lists up to 10 hours on a single charge.
• Jogging while keeping your ears open → Either, for different reasons. Both have open-ear designs. HAKII explicitly describes bone conduction and a silicone earhook; Monster emphasizes its lightweight, ergonomic fit.
• Listening without carrying a phone → HAKII Sole. It offers Bluetooth/MP3 dual mode and onboard storage, though the listed capacity differs between the feature details and title.
• Touch controls → Monster Open Ear AC360. HAKII uses physical push buttons, so the better choice depends on which control style you prefer.
• More listed Bluetooth range → HAKII Sole. Its stated range is up to 15 meters, compared with up to 10 meters for Monster.
• Calls during a workout → Monster has the clearer call-specific feature. Its listed DNN noise filtering is described for calls. The HAKII details do not provide an equivalent call-filtering claim.
• Choosing a headset for jogging and later gym use → Match the extra feature to your routine. Monster’s charging dock favors more total listening time; HAKII’s storage and IP68 rating favor phone-free workouts and swimming.
I would choose HAKII Sole if swimming or phone-free listening is part of my routine, because its IP68 rating and Bluetooth/MP3 mode are meaningful differences. For jogging alone, I would buy the Monster Open Ear AC360 if I valued its dock-assisted playtime and call-focused filtering more than onboard storage. My pick for the broader mix of running and water-based workouts is HAKII, with one important caveat: I would confirm its storage capacity before making the decision.
Before choosing, be honest about where and how you listen. If your runs are near traffic or other people, both products’ open-ear designs leave your ears uncovered, but open-ear listening does not guarantee that every surrounding sound will be easy to hear. Keep your volume and surroundings in mind.
Water protection is another dividing line. Monster’s IPX5 rating aligns with sweat and rain; HAKII’s IP68 rating is the one to consider for swimming. If swimming is not part of your routine, that extra protection may matter less than the battery arrangement, controls, or music-storage option.
Think about how you want to manage power. Monster’s up-to-24-hour figure includes the charging dock, while its stated single-use figure is up to 8 hours. HAKII lists up to 10 hours on a charge. Those figures describe different setups, so consider whether you prefer a dock-assisted total or a longer stated session before needing a charge.
Finally, the two models make different compromises around convenience. Monster supplies touch control and a lanyard, while HAKII uses push buttons and has an MP3 mode. If onboard playback is central to your decision, check the HAKII storage capacity carefully because its listed capacity figures do not match. For questions about price or current availability, check the current Amazon listing.
Both have open-ear designs suited to listening without enclosing the ear canals. Monster emphasizes a charging dock and call filtering; HAKII adds a silicone earhook, bone-conduction audio, and an MP3 mode. Choose based on whether battery flexibility or phone-free listening matters more.
HAKII is the swimming-oriented option in this comparison, with an IP68 waterproof rating. Monster is rated IPX5 for rain and sweat; its listed specifications do not describe it as suitable for swimming.
HAKII offers Bluetooth/MP3 dual mode and onboard storage. Its stated storage capacity is inconsistent across the product details, so confirm the capacity before buying. Monster’s listed features do not include MP3 playback or built-in music storage.
Monster lists up to 8 hours of use at a time and up to 24 hours with the charging dock. HAKII lists up to 10 hours on a single charge. The total figures are not directly equivalent because Monster’s longer figure includes the dock.
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