Hayabusa S4 Lace Up Boxing Gloves review

The Hayabusa S4 Lace Up is a distinct version of the S4 family: it replaces the standard S4's strap with traditional laces, lists 10, 12, 14 and 16 oz, and has manufacturer guidance for heavy-bag work, pad work and sparring. Its page also specifies single-layer foam splinting, injection-molded knuckle foam and a PU-engineered-leather shell. This is a source-based assessment, not a hands-on review; I have not worn, fitted, measured or tested the glove.

Keep the lace-up edition separate

The name matters here because a search result that shortens this to “S4” can hide a functional setup difference. The exact product page calls the closure a traditional full-palm lace system and labels the model “S4 Lace Up.” The standard S4 page is a hook-and-loop model, while the separately named S4 Youth and S4 Leather pages have their own selectors and construction descriptions. This assessment covers only the lace-up page and its 10–16 oz range; it does not import the standard S4's selector, an adult product's claimed use, or another model's cuff details.

The current page lists four ounce choices: 10, 12, 14 and 16. It does not show a color selector in the page text I reviewed, so the black-and-white image below identifies a pictured colorway rather than a color inventory. No public SKU is stated. A seller listing that says only “S4” is not enough to verify the laced version or its weight; check the title, selected size and the actual palm closure in the listing.

What the laces change in practice

Hayabusa describes the full-palm lace closure as secure and customizable. That is the manufacturer's design claim, not a measured result for every wrist. As a practical inference, laces generally involve more setup than a strap and may be difficult to tighten one-handed; the exact page does not describe tying time or whether help is required. If you train alone, rotate quickly between partners, or need to remove gloves without assistance, test the fastening routine before choosing this model. A lace closure also is not the same thing as a promise of better wrist support.

For athletes who already use laces and can tie them consistently, the distinguishing feature is the full-palm lace path rather than a hook-and-loop cuff. The page calls the fit customizable, but gives no wrist circumference, hand-pocket dimensions or lace tension target. Try the glove with your normal wraps if possible, and let an experienced coach or gym partner check how it closes instead of pulling harder to solve a poor fit.

Weight and activity: read the claim at its stated level

The manufacturer says this model is for heavy-bag training, pad work and sparring. Unlike product pages that map a smaller weight range to one activity and a larger range to another, the S4 Lace Up page does not attach a cutoff to any of its four sizes. The finder therefore treats the size and the listed uses as available within the same model-level plan; it does not claim that each gym accepts every size for sparring. Before partner contact, confirm the exact ounce weight and glove type with the coach or club. A published product description cannot override local sparring rules or say which weight is right for a particular boxer.

The 10–16 oz selector is useful for checking whether the exact listing offers a required number; it is not a measurement of the hand or a substitute for a fit check. Neither the page nor its size selector gives hand circumference or wrap-volume guidance. If the 16 oz maximum is too low for your gym's requirement, the S4 Lace Up page does not offer an 18 oz option even though some other S4-family or Hayabusa models have different ranges.

Splinting, foam and shell

The exact specifications call the wrist support “single layer foam splinting” and the knuckle protection “injection molded foam.” Those labels support a precise construction comparison: the page does not describe Dual-X, a four-Fusion-splint arrangement, multi-density padding or full-grain leather. The shell is specified as PU engineered leather, with nylon lining. A wipe-away-sweat microfiber thumb, attached thumb, aerated mesh palm and foam grip bar are also listed. Those details help identify the model, but they do not establish how it will feel, dry, protect a hand, or hold its shape after repeated sessions.

Do not read “splinted” as a clinical or injury-prevention result. The page provides no controlled test or independent certification for support or impact performance. If you have pain or a prior injury, consult a qualified clinician and your coach rather than selecting a glove by its marketing description.

Comparisons and buying checks

Compared with standard S4, the lace-up model's most consequential difference is closure, not a proven change in padding performance: both pages describe single-layer foam splinting, injection-molded knuckle foam and PU-engineered leather. Compared with the older T3 Lace Up assessment, the S4 page is a current named product reference with a 10–16 oz selector and explicitly lists bag, pad and sparring use; the T3's earlier status and evidence belong to its own page. These distinctions are more useful than assuming that a family name makes every S4 or T3 configuration interchangeable.

Before ordering, verify “S4 Lace Up” rather than standard S4 or the earlier T3 Lace Up; check that the selected size is 10, 12, 14 or 16 oz; inspect that the listing is the black/white lace-up pair if that is the intended design; and confirm the gym accepts the exact size for the chosen session. Check fit with wraps and ask who will lace the glove. My practical conclusion is narrow: this model has a clearly documented lace closure and broad activity statement, but its page leaves size-by-session guidance, hand measurements and individual fit unresolved.