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Sawyer’s Bonding Base Technology

The Sawyer Stay-put sunscreens bond to the skin in a unique way that give you the best and most comfortable protection you have ever experienced. Think of it as a “breathable matrix”. While most sunscreens hold the lotions in the top two layers of skin, Sawyer’s Stay-put sunscreen also “bonds” the sunray absorbing agents deeper into the skin. This formula was engineered to spread the same volume of lotion over a larger cubic area of skin, necessitating less lotion and with less sunscreen lotion per area of skin; you get a more comfortable, breathable feel.

You will hardly even know you have sunscreen on. And because our sunscreen is designed to go deeper into the skin, it will be less likely to rub off during activities, unlike less effective surface lotions. Your skin has many layers of cells from the base (basal level) to the top. Theses cells are constructed sort of like the Grand Canyon on a micro scale. That is how sweat can be generated at the lowest levels and pass to the top. Sawyer’s Stay-put sunscreens use a special technology to bond the ray absorbing agents to the sidewalls of the canyon. Thus, sweat and water pass over the compounds without flushing them away. This makes the formulas highly resistant to deterioration due to sweating or swimming, and it is still very comfortable to wear.


How SPFs Works

The chart to the right demonstrates how SPF’s are calculated. In reality you very seldom need more than an SPF30 which blocks out or absorbs 97% of the sun’s rays. To achieve an SPF of 45 or 50 manufacturers have to add 25% to 50% more absorbing agents while achieving very little in the way of skin protection, absorbing only an extra 1 or 2%. Your body can naturally handle around 17% of the rays without burning so you are thus packing your skin with lots of extra absorbing agents yielding essentially no additional protection.

This is why we highly recommend that you start with our SPF 30 formula and only move to a higher SPF in the case of intense situations (as described below) if needed. If you go strictly by the math you see that you only need an SPF of 6 or 8 to get enough protection to supplement the body’s natural protection. But since 90% of the population under applies sunscreen relative to the FDA “dosage” we recommend using our SPF30 because an under applied dosage of SPF30 will give you enough absorbents to protect you.

UVA rays are often referred to as the “wrinkling rays”. This is really only true of the shorter UVA rays (see the chart to the right) and any good SPF 30 formula will get those rays even if they do not absorb the longer non harmful UVA rays.



Skin Sensitivity To UVB And UVA Rays


SPF Level % of UVB Sunrays Absorbed % of Formula that is Heavy Oil (Absorbers)
45 98% 50 to 60%
30 97% 40 to 50%
15 93% 30 to 40%
8 88% 20 to 30%
4 75% 15 to 25%


New FDA Regulations

In response to industry pressure the FDA issued new label guidelines for sunscreens (the use of the word sunblock is no longer allowed) requires protection against the entire spectrum of UVA rays in order to use the term “Broad Spectrum” sunscreen. Unfortunately the only way to achieve absorption of the longest UVA rays is to use a chemical called Avobenzone. You will see this feature highly touted beginning this year.

Sawyer WILL NOT add Avobenzone to its formulas for two reasons. First is that the longer UVA rays are not harmful to your skin as shown in the chart and therefore do not need to be absorbed, and Secondly Avobenzone is not stable in natural light and as it dissipates it removes with it some of the other sunscreen absorbents. Therefore not only will the labels for the products containing Avobenzone recommend reapplications every two hours, you will need to do so or risk getting burned. Sawyer’s bonding base formulas have a great reputation for how long they last and even though we will also have to change our labels to recommend frequent reapplications we think the people who have used our tried and true formulas in the past will appreciate how well they will continue to work while other brands may not be as good as they were before the new regulations.



Learn more about Our Sunscreen Recommendations.
Learn more about Different Types of Sunscreen Formulas & How They Work in the Skin
Learn more about Different types of sunscreen bases
Learn more about the latest Sunscreen News.
Learn more about UVA and UVB
Learn more about How the sun affects your layers of skin.


  • Q: ViewWhat is the shelf life of your sunscreen?

    Our Stay Put sunscreens have an expiration date of ~3 years when stored properly in a cool, dry location.

  • Q: ViewCan I wear a repellent with a sunscreen?

    You can definitely use sunscreen and insect repellent together. We recommend applying the sunscreen first. The trick to a comfortable and effective application of sunscreen is to put it on at least 10 minutes before sun exposure. This will allow ample time for the sunscreen to fully absorb into the skin before your body gets warm out and about in the sun.

    Once the sunscreen has dried, you can apply the insect repellent. Sprays are often most convenient but a nice comfortable topical insect repellent lotion will typically last longer and also be more resilient to swimming and other active use. Our SPF 30 is a very breathable and long lasting formula that pairs better with insect repellent than most other sunscreens on the market.

  • Q: ViewWhen should I re-apply a sunscreen?

    Above the skin sunscreen needs to be re-applied much more frequently than below the skin sunscreens, but replacement of each depends on several environmental factors and also the quality of the sunscreen. Keep in mind the following factors which affect sunscreen effectiveness:

    Type of Sunscreen: Film, Wax or Bonding Base
    Time of Day: Peak Sun is 10:00 a.m. to 3:00 p.m.
    Time of Year: Peak Sun is May though July
    Pre-Tanning of the Skin: Your skin is more susceptible in the spring and early summer than it is after you have some level of tan base.
    Areas of Thin Skin: Nose, Ears, Forehead, Top of Head, Top of Feet, and Shoulders need extra Sunscreen and attention because they have less layers of skin to protect themselves.
    High Altitudes: Above 6,000 feet significantly increases your exposure to sunrays.
    Higher Altitudes: Above 10,000 feet offers very little natural protection at any time of the year.
    Low Latitudes: The closer you are to the equator the greater your ray intensity. People in Northern climates vacationing in Southern climates are particularly vulnerable.
    Exposure to much Rubbing or Flushing: Frequent towel drying or water skiing removes Sunscreen at a much faster pace than other activities.
    Profuse Sweating: May cause Sunscreen, especially above the skin Sunscreen, to migrate.
    Use with Insect Repellents: May cause the loss of up to 30% of the SPF protection level.

    If your environment includes several of the above, you may need to consider using a higher SPF level or more closely monitor your skin, especially the areas of thinner skin. If your environment includes more than several of the above, then you really need to watch your skin closely and take other precautions as well, such as more sun protecting clothing, hats, and staying out of the sun at peak times.

  • Q: ViewWhat SPF do I need? How much do I need for a trip?

    If properly applied (1 1/4 ounces per full body coverage) you seldom need more than an SPF 15. See the paragraph below for when you may need more. However, most people put on only half of the recommended FDA standard. A SPF 15 applied at half rate is effectively a SPF 7, better than nothing but still not a true sunscreen. If you can discipline yourself to put on a generous amount, then after it has fully absorbed into the skin, you will benefit by having less chemicals in the skin which allows your skin to breathe easier. If you just can’t bring yourself to lather it on then jump to a SPF 30 which, when half applied, still leaves you with an effective protection of a SPF 15. If you’re sensitive to oxybensone or benzephenone then stick with the SPF 15 which generally does not include that sunscreen.

    In planning a trip, use the 1 1/4 ounces per person per day figure as a guideline. If you’re building a tan, or reducing your skin exposure via clothing, then reduce your anticipated need accordingly. Keep in mind that a soaked cotton shirt yields protection equivalent to only a SPF of 4 to 8 only and therefore you may need to wear a sunscreen below the shirt if exposed to water or sweat.

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Available at:

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  • Amazon
  • Bass Pro Shops
  • Cabela’s
  • Dick’s
  • Menards
  • Moosejaw
  • REI Co-Op
  • Walmart

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