$10 - $15

93575 LensPen Optics Cleaning Tool by Celestron

How many times has dust or lint on your eyepiece or telescope ruined an observing session? One innocent-looking strand of hair strewn across the lens in your photos or astroimages can take hours of clean-up in a photo-editing program, and a greasy thumbprint or smudge on the optics can send an otherwise perfect image to the trash. Enter the Celestron LensPen, a dual function optical cleaning tool that is small and lightweight enough to stay in your telescope accessory case or camera bag so it will always be there when you need it.

The LensPen is two cleaning tools in one. One end contains a soft brush for removing dust and other particulates from any optical surface. The opposite end of the LensPen will handle the smudges and spots that cannot be brushed away. This tool has a special cleaning tip that works without the need for liquids, so it will never dry out. A cap protects the smudge removal tool when not in use, while the brush retracts safely inside the LensPen.

When cleaning optics, it is always best to use the brush first, even if you think it unnecessary. Carefully brush the entire surface, and when you are done, inspect your work. If you find any smears or spots, use the cleaning element to remove them, using a light touch.

The Celestron LensPen is a great tool for all of your optical equipment, including eyepieces, telescopes, spotting scopes, binoculars, microscopes, cameras, lenses, and more.

• Keep your optics clean with the innovative LensPen
• Use the soft retractable brush for removing loose particles & dust
• Clean smudges, fingerprints, pollen, and other sticky substances from the optics with the special cleaning element.
• No liquids are used...nothing to spill or dry out.
• The LensPen is safe and easy-to-use. Keep one handy for all your optics!

TDSK1413/P Conductivity Solution, 1413uS KCl, 1Pt. by Sensorex

TDS/Conductivity instruments and sensors must be calibrated together. For a single-point calibration, select the one solution that approximates the expected conductivity or ppm level of total salts. Mixed Salt standards are the most frequently used in the field to sample naturally occurring water sources, boiler feed water, or cooling tower water. Typical river water, well water, or lake water sample will contain a mixture of several different salts. Sensorex Mixed Salt standards simulate a "Natural" mixture of common salt compounds found in these sources. Sodium sulfate, sodium bicarbonate, and sodium chloride salts are blended to provide a representative value. There are certain applications where Single Salt Solutions are preferred. NaCl Solution is routinely used to calibrate instruments measuring Sea Water or brackish water samples. Reagent grade salt and high resistivity DI water is compounded for accurate results. KCI Single Salt Solution may be used with conductivity meters that read directly in Siemens or Ohms. KCI (potassium chloride) is established as an international calibration standard for conductivity measurement. Choose the conductivity calibration solution that is right for your application. CA Residents: Prop 65 WARNING(S)

08080-81 Stainless Steel Bimetal Pocket Thermometer, 1.75" Dial, Glass Lens, 8" Stem, -50 to 100C, 2F Div by Digi-Sense

• Factory tested to three points with a ±1% accuracy
• Minimum immersion: liquids 2" (50 mm), gases 4" (100 mm)
• Hermetically sealed dial stops internal fogging
• Recalibrate using external adjustment nut
• 304 Stainless Steel dial case and stem
• Shock resistant

Includes

All thermometers come with a statement of test and a beaker clip.

A-1503 Ammonia in Seawater Accessory Pack by AquaPhoenix

The A-1503 Ammonia Accessory Pack is used in conjunction with test kit K-1513 for seawater analysis.

The Ammonia in Seawater Accessory Pack supplies enough of each solution to perform approximately 30 tests.

Qty per pack: Two 20-mL bottles of A-1504 Stabilizer Solution, one 20-mL bottle of A-1502 Activator Solution, and one 1.0-mL syringe