$25 - $50

TT91V Class 9 TDG Label (Vinyl) by GHS Safety

Shipping Labels are essential for packages that contain dangerous goods. GHS labels are available in two materials. Paper for indoor applications and in vinyl for extended outdoor usage using a fade resistant ink. These labels meet the UN Recommendations on the Transport of Dangerous Goods.

Available in 500/roll formats.

TK4030-Z Chlorine OTO Residual Test Kit by AquaPhoenix

• Refill Reagents: OT1510-B

*Please note we can only ship RKI products to customers within the United States

*Please note we can only ship RKI products to customers within the United States

*Please note we can only ship RKI products to customers within the United States

K-7370S COD Vials, 0-15,000 ppm (HR+) Not USEPA Approved, 25 vials by AquaPhoenix

All COD Kits require the use of a Digestor Block and the V-2000 Photometer, an A-7325 COD Photometer, or a spectrophotometer capable of accepting a 16 mm round cell. Photometers sold separately. A digestor block is no longer available from CHEMetrics.

A fresh reagent ampoule blank must be prepared for each series of tests; therefore the number of samples that can be tested with each kit will vary.

0590 0010 Set 2mm Test Leads (90° plug) by Testo

These high-quality standard measuring cables with an angled plug and an 0.7 inch long tip can be attached to Testo clamp meters, Testo digital multimeters or other makes of multimeter. The rubber-coated grips of the standard measuring cables offer a secure hold and so ensure easy measurement of electrical parameters.

• CAT II 1000 V measurement category
• Tip Ø: 0.07 in.; tip length: 0.7 in.
• 1 set of measuring cables with angled plug

Includes:

1 set of standard measuring cables (angled plug), tip &Oslah;: 0.07 in.; tip length: 0.7 in.

*Please note we can only ship RKI products to customers within the United States

Part Number: HU-INCONN

*Please note we can only ship RKI products to customers within the United States

TDSNA13.4 Conductivity Solution, 7501ppm/13,400uS, 1Qt 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)

18527-18 Standard Type-J Thermocouple Male Connector, 2 Pin, Hollow by Digi-Sense

• Molded barriers prevent short circuit and the solid pin design ensures good contact even in demanding applications
• Miniature connectors are suited for small wires and mineral insulated cables
• Connector-body color is brown, calibration type (J or K) is printed on the body

93618 M42 Spacer Kit by Celestron

To achieve the best astroimages, it is important to attain the proper back-focus distance for your camera relative to the telescope it is being used with. If the back-focus distance your camera consumes is not exact, the performance at the corners of full frame imaging sensors will suffer—stars will appear elongated and not as pinpoints.

Example: RASA 8 with a ZWO ASI 183 MC PRO camera

• Required back-focus distance for RASA 8 with included M42 camera adapter: 25mm
• Back-focus consumed by ZWO ASI 183 MC PRO camera: 17.5mm
• To achieve equal back-focus distance, a 7.5mm M42 spacer ring is required

Celestron's M42 Spacer Ring kit includes three different length spacer rings to achieve the proper back-focus distance with our popular Celestron optical tubes and T-thread camera adapters.

How to Use

Depending your method of astrophotography (DSLR or CCD/CMOS), there are two ways to use the M42 Spacer Ring. If you are using a DSLR, place the desired M42 Spacer Ring between your T-Ring and your T-Adapter for your optical tube. If you are using a CCD or CMOS camera, place the desired M42 Spacer Ring between the camera and the T-Adapter for your optical tube.

Body

The M42 Spacer Rings are machined aluminum black anodized. The internal surfaces are blackened and glare-threaded to provide the highest contrast. Each spacer ring has a knurled surface, providing a great gripping surface for threading/unthreading. The M42 Spacer Rings are compatible with M42 x 0.75 (T-thread) camera adapters.

• Adjusts back-focus between your camera and telescope for the best astroimaging results
• Kit includes 3 spacer rings of different lengths (7.5mm, 12mm, 30mm)
• Threads to your T-Ring and T-Adapter with standard male and female T-Threads