$150 - $200

AI3105 LabSen 251 Glass-body Spear pH Electrode for Semi-Solid Samples by Apera

Built with proprietary sensor technology and premium materials from Switzerland, Apera LabSen 251 Glass-body pH Electrode is designed for direct pH test of semi-solid samples as well as general water solutions.

LabSen S-type spear glass membrane - low resistance and high firmness, rendering fully stabilized readings in 15 to 30 seconds, and is yet 10 times stronger than traditional glass membranes, highly resistant to general impact, eliminating the chance of accidental breakage when inserting into semi-solid samples.

Open&Ceramic double-junction with Polymer electrolyte - ensures full contact with test samples while minimizing junction clogs. No need to refill electrolyte.

Long-Life Reference System - composed of a glass tube, AgCl, and a reference silver wire. The top end of the slim glass tube is stuffed with cotton, which prevents the reaction between AgCl and electrolyte when the temperature changes. It improves the stability of reference electrode and extends the service life of the electrode.

The electrode uses a standard BNC connector, compatible with any pH meters that use BNC connectors. No temperature sensor is built-in. Users need to have a separate temperature probe (ex: Apera MP500) to enable ATC or manually input temperature to achieve temperature compensation.

• Spear sensor designed for direct pH test of semi-solid samples
• LabSen S-type glass membrane, featuring fast response and high firmness
• Open&Ceramic double-junction with Polymer electrolyte
• Long-Life Reference System - improves the stability of the reference and extends the electrode's service life

Old Part Number: 102810N
New Part Number: J102810PN

Part Number: J197150LM6

94175 Reducer/Corrector f/6.3 by Celestron

This combination focal reducer and field corrector lens accessory works with all Celestron 5", 6", 8", 9 1/4", 11" and 14" Schmidt-Cassegrain telescopes. This clever accessory makes it possible to have a dual focal ratio instrument, without sacrificing image quality. The Reducer/Corrector is f/6.3 for C5, C6, C8, C9¼ and C11 telescopes and f/7 for the C14 telescope.

If offers wide fields of view with any Schmidt-Cassegrain telescope. Used for astrophotography, it reduces exposure time by a factor of 3.

Celestron doesn't offer a f/6.3 Schmidt-Cassegrain telescope, because the design is impractical, with a large central obstruction, and resulting loss in contrast. This, added to the inability to utilize longer focal ratios for certain objects, led Celestron to design the four-element, fully multicoated f/6.3 Reducer/Corrector. Results are amazing both visually and photographically.

AI3102 LabSen 221 Glass-body pH Electrode for Viscous and Low Ion Concentration Samples by Apera

Built with proprietary sensor technology and premium materials from Switzerland, Apera LabSen 221 Glass-body pH Electrode is designed for titration and low ionic strength solutions as well as general water solutions. The electrode is compatible with TRIS buffer solutions.

LabSen S-type cylindrical glass membrane - low resistance and high firmness, rendering fully stabilized readings in 15 to 30 seconds, and is yet 10 times stronger than traditional glass membranes, highly resistant to general impact, eliminating the chance of accidental breakage.

Movable Sleeve Junction - easy to clean, especially suitable for low ionic strength solutions, emulsions, and suspensions. The infiltration rate of the electrolyte can be adjusted by the tightness of the sleeve.

The electrode uses a BNC connector, compatible with any pH meters that use BNC connectors. No temperature sensor is built-in. Users need to have a separate temperature probe (ex: Apera Instruments MP500) to enable ATC or manually input temperature to realize temperature compensation.

• Built with LabSen S-type glass membrane, featuring fast response and high firmness
• Movable Sleeve Junction - easy to clean, adjustable infiltration rate
• Long-Life Reference System, improving the stability of the reference and extends the electrode's service life
• No more air bubbles inside the glass membrane thanks to the Swiss blue gel electrolyte.

28145 Si-TH4 wireless temperature-hygrometer (psychrometer) probe by Sauermann

This wireless psychrometric probe provides accurate indoor and outdoor temperature and hygrometry measurements to work on air conditioning, refrigeration and heat pump installations.

The Si-TH4 calculates dry and wet bulb temperatures quickly and easily, using a flexible probe with a sliding magnet for convenient positioning. It connects easily to the Si-RM350 and Si-RM450 manifolds, as well as to the mobile application Sauermann Pilot.

LabSen 553 Plastic Combination Spear pH/Temp. Electrode by Apera

Backed by proprietary Swiss sensor technology and materials, the LabSen® 553 3-in-1 pH/Temp. Spear Electrode/Sensor/Tester is designed for testing soil directly (This is a replacement probe for Apera PH850-SL, PH9500-SL).

Long-Life Reference System - The LabSen 553 pH electrode adopts a long-life reference system, which is composed of a glass tube, AgCl and a reference silver wire. The top end of the slim glass tube is stuffed with cotton, which prevents the reaction between AgCl and electrolyte when the temperature changes. It improves the stability of reference electrode and extends the service life of the electrode.

Polymer Electrolyte - The solid polymer electrolyte makes the electrode hard to be contaminated and maintenance-free.

Special Glass Membrane - The LabSen 553 pH electrode adopts a spear sensor tip, which is ideal for directly testing semi-solid samples like soil.

Compatible Apera Instruments' meters: PH700, SX823-B, MP511, PH800, PC800. May NOT work with other brands' meters because the temperature unit might be incompatible. The electrode is backed up with a 6-month warranty by Apera Instruments.

• Proprietary pH sensor technology and materials from Switzerland
• Special LabSen Spear pH sensor tip, ideal for direct soil pH testing. No more slurry making.
• Pom housing, ideal for use in harsh environments
• Polymer electrolyte - not more clogged junction
• Long-life reference system, improving the stability of reference electrode and prolong the service life of the electrode

Part Number: J197150LM18

Old Part Number: 126525
New Part Number: J126525LA

93527 2" Mirror Diagonal with XLT by Celestron

There are few telescope accessories that work as hard or matter as much as a diagonal! An integral part of the optical chain, a good diagonal can make a big difference in the quality of the image you see. A 2" diagonal is required if you want to use 2" eyepieces when observing with your telescope. The larger 2" barrel allows you to see a bigger percentage of the telescope's light cone, which works wonders for capturing faint deep sky objects with low surface brightness.

The Celestron 2" Mirror Diagonal was built for superior performance. The housing is machined with precision instruments to make sure the optics stay perfectly aligned. The diagonal's mirror is tested with an interferometer, and is guaranteed to be 1/10 wave or better. The mirror's surface is covered with the same high performance XLT coatings used on Celestron's best telescopes, and the result is a sharp, bright image that will satisfy the most discriminating amateur astronomer.

This 2" diagonal threads securely to the rear cell of standard Schmidt-Cassegrain telescopes. To take advantage of the XLT Diagonal's extra light throughput, insert a 2" eyepiece into the barrel. If you want to use 1.25" eyepieces, slide the included 2" to 1.25" adapter into the eyepiece barrel and secure it with the thumbscrew. When you're not observing, store your diagonal in the included aluminum case for protection.

• 2" SCT mirror diagonal with high performance XLT coatings.
• 1/10th wave mirror is tested with an interferometer to ensure quality.
• Housing is precision machined to achieve and hold good optical alignment.
• Includes a 2" to 1.25" adapter and aluminum carry case.