A 350cc breast implant often weighs about 340–380 g (12–13 oz), depending on saline vs silicone gel and shell thickness.
When people ask about implant “weight,” they’re usually trying to predict two things: what the scale might show and what their chest might feel like day to day. The phrase how much do 350cc implants weigh? pops up a lot because 350cc is a common mid-range volume. The good news is that the math is straightforward once you know what “cc” means and what parts of the device add mass.
| What You’re Measuring | Typical Range | Why It Varies |
|---|---|---|
| Fill volume (the “350cc” part) | 350 mL of fluid or gel | “cc” is a volume unit, not a weight unit |
| Saline fill weight | About 350–355 g | Normal saline is close to 1 g per mL, with small temperature shifts |
| Silicone gel fill weight | About 325–360 g | Gel density differs by formula and model |
| Outer shell and patch | About 20–40 g | Shell thickness, surface, and size change the silicone elastomer mass |
| Valve and fill tube (saline only) | About 2–10 g | Depends on the valve design and model |
| Total weight per implant | About 340–400 g | Fill + shell + any valve parts |
| Total added weight (both sides) | About 680–800 g (1.5–1.8 lb) | Two implants add up fast, even when each feels modest in hand |
| “Feel” on the chest | Varies by body | Placement, tissue coverage, and bra fit can matter more than grams |
What 350cc Means In Implant Sizing
A “cc” is a cubic centimeter. In medical device sizing, it’s used like a milliliter: 1 cc = 1 mL. So “350cc” tells you the internal volume of filler, not the outer dimensions, not the profile, and not the weight.
Two implants can both be labeled 350cc and still look different because shape can shift the footprint and projection. A wider, lower-profile 350cc spreads volume out. A narrower, higher-profile 350cc pushes it forward. Both still hold the same volume.
How Much Do 350Cc Implants Weigh?
Here’s the quick math. A mental model is “one cc is near one gram.” That puts the filler close to 350 g. Then you add the shell and any valve parts.
On a scale, a single 350cc implant often lands in the low-to-mid 300-gram range. In ounces, that’s around 12 to 14 oz per implant. Two implants together are often near 1.5 to 1.8 lb.
350cc Implant Weight In Grams And Ounces
If you want the numbers laid out, start with a simple conversion:
- 350 cc = 350 mL of filler
- 350 g = 12.35 oz
- 350 g = 0.77 lb
That 350 g figure is the filler only. The silicone outer shell adds extra mass. One published surgical reference shows a 450 mL saline implant shell weighing 35 g, which gives you the right scale for shell weight on devices in this range. Smaller volumes can weigh a bit less, and thicker shells can weigh more.
If you’re comparing saline and silicone gel, the gel itself can be a touch lighter or heavier per cc based on its density. Some technical sources list silicone gel densities under 1 g/mL, while other published measurements for certain implant lines report densities over 1 g/mL. That’s why two “350cc” implants from different families can land on different totals.
Why The Number Changes Between Saline And Silicone
Both saline and silicone gel implants use a silicone outer shell. The main differences that shift weight sit inside that shell.
Saline: Close To Water Weight
Medical “normal saline” is water with salt at 0.9%. Its mass per milliliter is close to water, so a 350 mL fill comes out close to 350 g. Add the shell and valve hardware, and the total usually lands higher than the fill alone.
Silicone Gel: Density Depends On The Model
Silicone gel isn’t one single recipe. Gel firmness and other design choices can shift density. Some gels land under 1 g/mL; others measure over 1 g/mL in published reports. So, two 350cc silicone gel implants can differ by a few dozen grams even before you count the shell.
Shell Thickness And Surface Finish Add Mass
Shells aren’t all equal. Thickness can change to meet strength targets, and surface design can change the total amount of silicone. Those choices add grams you won’t see in the “cc” number.
What The Added Weight Feels Like Day To Day
People tend to overestimate what 350 g feels like in the hand and underestimate how it feels when it’s carried on the front of the torso. Weight on the chest can change bra strap pressure, posture cues, and how certain tops sit.
Still, “feel” isn’t just weight. Placement and tissue coverage matter. An implant placed under the pectoral muscle can feel different from one placed over it, even at the same volume and mass. The same goes for how much natural tissue you already have.
If you do lots of running or jump-heavy training, motion matters. A supportive sports bra can make a bigger difference than shaving a small number of grams off an implant choice. When people say an implant “feels heavy,” it’s often strap tension, bounce, or a band that’s doing all the work.
How To Get A More Exact Answer Before You Commit
Online answers are averages. Your final weight depends on the exact device model and how it’s filled. Here’s a simple way to tighten the estimate:
- Ask for the brand and model name (not just “350cc silicone”).
- Ask whether the listed volume is the nominal fill or the planned fill.
- Ask what valve system is used if you’re choosing saline.
- Ask whether the plan includes any overfill or underfill within the manufacturer’s range.
The U.S. Food and Drug Administration keeps a central breast implants page that explains the two approved fill types and the basics of labeling and risks. The American Society of Plastic Surgeons notes FDA screening for silicone devices often starts 5–6 years after placement, then repeats each 2–3 years on its Breast Implant Safety page.
When 350cc Isn’t Filled To 350
With saline implants, “350cc” can describe a target volume, but the final fill can sit within an allowed range. Surgeons may fill slightly under or over the nominal number to fine-tune shape, firmness, or symmetry. That means two people can both say “350cc saline” and still carry a different number of grams.
If you’re planning around weight for sports bras or shoulder comfort, ask for the planned fill in cc, not just the implant’s labeled capacity. Then apply the same math: milliliters translate to grams in a near 1:1 way for saline, plus the shell and valve parts.
Why Cup Size Predictions Don’t Match 350cc
It’s tempting to translate “350cc” into a bra cup change. Real life is messier. Band size, breast width, skin stretch, and implant profile all change the look. Two people can get the same 350cc implant and end up buying different cup sizes.
Also, bras aren’t a lab tool. Brands vary, and styles vary. If you want a more reliable visual, surgeon photo galleries sorted by implant size and body measurements tend to beat cup-size promises.
Numbers For Quick Mental Math
When you’re comparing sizes, it helps to keep a simple set of rules:
- Per implant: volume in cc is near grams of filler.
- Per pair: double it, then add 40–80 g for both shells together as a ballpark.
- In pounds: grams ÷ 454 = pounds.
That shell add-on is a ballpark because shell weight changes with device design. Still, it keeps your estimate from being too optimistic when you’re planning for two implants.
| Implant Size | Added Weight Per Pair | What That’s Like |
|---|---|---|
| 250cc + 250cc | About 0.55–0.65 kg (1.2–1.4 lb) | Two full soda cans |
| 300cc + 300cc | About 0.65–0.75 kg (1.4–1.7 lb) | A small laptop |
| 350cc + 350cc | About 0.70–0.80 kg (1.5–1.8 lb) | A pair of running shoes |
| 400cc + 400cc | About 0.80–0.90 kg (1.8–2.0 lb) | A big hardcover book |
| 450cc + 450cc | About 0.90–1.05 kg (2.0–2.3 lb) | One liter of water |
| 500cc + 500cc | About 1.00–1.20 kg (2.2–2.6 lb) | A filled kettle |
| 600cc + 600cc | About 1.25–1.45 kg (2.8–3.2 lb) | A small bowling ball |
| 700cc + 700cc | About 1.45–1.70 kg (3.2–3.7 lb) | A big bag of rice |
Common Mix-Ups That Make The Math Look Off
Confusing “cc” With Cup Size
Volume is one piece of sizing. Cup letters depend on band size and how a bra brand cuts fabric.
Forgetting Shell And Valve Mass
People sometimes quote “350 g” as if it’s the full device. That’s the filler only. The shell and valve parts add extra grams.
Comparing Across Brands Without Noticing Profile
A 350cc high-profile implant can look and feel different from a 350cc moderate-profile implant because the same volume sits in a different shape.
Bring-This List For Your Appointment
If you want a no-drama way to nail down the details, take this checklist with you and fill it in during your visit:
- Brand and model line
- Planned volume per side (cc)
- Surface type (smooth or textured)
- Shape (round or anatomical)
- Placement plan (over or under muscle)
- Warranty and rupture coverage details
- Screening plan and timing
- Your current bra band size and width notes
Once you have those details, you can plug the final cc into the simple math above and get a weight estimate that’s close enough for planning bras, workouts, and packing. If you’re still wondering how much do 350cc implants weigh? after that visit, ask for the device spec sheet weight for the exact model you picked. Save those details; they help you later, too.