Miso Clinic · Treatment guide

Density 300 shots versus 600: what is the difference?

“300 or 600?” is the obvious question when you look at a price list. Once you know what a “shot” is, the question looks a little different.

Treatment guideAbout a 5-minute readSeptember 2026Miso Clinic, Daegu · Dr. Lee Chi-Hak

The short answer

a shot is a specification, not a dose. One RF shot is one energy pulse, and the total is not set by the practitioner; it is sealed into the single-use tip. The market’s 300, 600 and 900 are multiples of tip specifications. And no human study has randomised 300 against 600. The manufacturer manual of the longest-used monopolar device sets the endpoint as the heat the patient reports, not a shot count. So the number follows the area and number of zones treated; more is not better.

What one shot is

The tip is placed on the skin and delivers energy once for a fixed time. That is one shot. Tips are single-use and stop delivering when the sealed count is used up. US device registration lists Thermage-class tips as “eye, 0.25 cm², 450 pulses” and “total, 4.0 cm², 600 pulses”. So “how many shots” really means “how many tips”.

What actually differs between 300 and 600

What shot count really changes
300 shots600 shots
Area coveredPart of the face (one or two zones)Whole face, or face plus part of the neck
Overlap on the same spotLessCan overlap more
Evidence of a better resultNoneNone — no comparison exists
Evidence of more adverse eventsNoneNone — no dose-response study

So 600 is not “twice the effect” of 300. It is twice the area, or more overlap on the same area. Which is better has never been compared in humans.

How Miso Clinic decides

  • Where the sagging is comes first, by examination: jawline only, cheeks too, neck too.
  • Count follows zones and area. One or two zones lands near 300; the whole face near 600.
  • The endpoint is heat feedback. The goal is the right heat in each zone, not using up the shots.
  • We do not suggest 900 by default. 900 came from a Korean physician survey, not a society guideline.

The same 300 shots is a different amount on a different tip

300 shots on a 3 cm² tip and 300 on a 0.25 cm² eye tip differ twelve-fold in nominal area. So another clinic’s “300” and ours are not the same amount. When comparing, ask which tip, on which area.

Which treatment fits which concern

Which treatment fits which concern
ConcernTreatments to considerWhy
Jawline onlyDensity, around 300Set by number of zones
Cheeks, jawline and foreheadDensity, around 600Set by area
Eyes onlyEye tipSmall area; shot comparisons are meaningless
Thin skin, mild saggingBooster class firstMay not be the RF layer

Which treatment is “best” is decided by the state of your skin right now, not by the product. In consultation we look first at what has been lost and what is still there, before we talk about any product name.

Frequently asked questions

Is 600 twice as effective as 300?

No. Twice the area, or more overlap, and no human comparison of which is better.

More shots, more side effects?

No dose-response study exists. “Do not re-fire immediately on the same spot” is a long-standing recommendation, though.

I was offered 900. Is that normal?

900 is the figure 86.3% of 82 Korean physicians called “appropriate” in a survey, not a society guideline. It is fair to ask why 900.

What if shots are left over?

Tips are single-use, so leftovers cannot be kept. That is why choosing the tip to match zones and area matters from the start.

Read next

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Who wrote this

Written and reviewed by Lee Chi-Hak, MD, medical director of Miso Clinic in Daegu, South Korea. Studies are cited with their size and limitations, and where we could not find data we say so. Individual decisions need an in-person examination; this page does not replace one.

Miso Clinic
Medical directorLee Chi-Hak, MD
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References

  1. Jeisys Medical, Density product material — sequential monopolar → bipolar RF, 6.78 MHz, up to 400 W, RIC impedance correction, five-level gas cooling, four tips (ALPHA, Eye, Face, Body). MFDS-approved medical device.
  2. Density human study — 16 people, 3D measurement 0.82 ± 0.36 mm, no control group.
  3. 2026 systematic review (15 studies, 1,230 people, one RCT) — states that no head-to-head comparison between RF devices was identified.
  4. Thermage CPT Technical User’s Manual (Solta, 2021) — treatment endpoint is patient heat feedback (2.0–2.5 on 0–4), not shot count. US GUDID tip specs: EYE 0.25 cm² 450 REP, TOTAL 4.0 cm² 600 REP.
  5. Suh DH et al., Dermatol Ther 2017;30(5):e12536 — survey of 82 Korean physicians, 86.3% agreeing with 900 shots for the face.

Everything on this page is general information and does not replace medical diagnosis or treatment. Effects and side effects vary with individual skin condition, age and underlying illness, and the same result is not guaranteed for everyone. Any decision to proceed should be made in an in-person consultation with a physician.

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