Our each is (4) of the blue plastic "D" Cell modular battery holders, approx 3-3/8" x 1-7/16" x 1-1/8" deep without tabs. They slide together either side-to-side or end-to-end or any combination of both, with connecting tabs in both directions. Can be wired parallel or in series. Open tops. Interesting possibilities.

Nice little pulley unit kit includes (1) pulley each at 50, 30, 25 and 20mm and (3) pulleys at 11mm, plus myriad bushings, a 3VDC motor, (2) belts and a belt guide, base, mounts and assorted hardware. Includes graphic assembly instructions, plus a couple of rudimentary drawings with suggested projects. It's a mechanical science project waiting for a home.

This 3-5/16” dia double-sided wire gauge wheel measures from 0-36 AWG on one face and from .005" to .325" on the other. It’s for non-ferrous metals, which is pretty much all of what you run across anyway, unless you’re Ferrous Bueller.

How do you clean your loose precious gems? The professionals use this two-piece brass mesh cleaning basket. Unscrew the halves, pop your stones inside, put it back together and soak it in your cleaning solution. Measures 23mm (0.90") and would also do for very small machine parts. You can probably think of even more clever uses. Please let us know if you do.

This torquey take-out 6-24VDC (12VDC nominal) motor draws approx 250mA no load, stalls at 7.2A and spins approx 5700 rpm. Measures 2" x 1-13/32" with a 3/4" x 1/8" flattened shaft and may have a setscrew-mounted coupler that resembles a router bit. Has prewired leads. Mabuchi part no. RS-545SH.

In nylon digital camo, this military radio bag measures 11" x 12" x 6" with adjustable straps on the side panels to pull them in, another to close the top, and a pair of female molle buckles to attach it to something else. Sew it all together, add a strap and you’ve got a great carry-all. Note openings at bottom corners. For you collectors, it’s marked  "APB03 RADIO POUCH SPM1C1-09-F-C002 8465015158636 F190686393 TAMCN NO. C54402F"

We’d start with triops, lovely little crustacean-ettes that have been around since Triassic days. You pick the Ghost Triops, see-through honeys, or the larger Gigantic Triops (gigantic among lesser beasts). In both cases you get eggs, baby and adult food, and a pipette. You add a bright light source, bottled natural spring water and a small tank. They hatch in a day or three, are full grown in a month or so, and have a life-cycle of up to 90 days.  Ages 8+.

The manufacturer, Elenco Electronics, says Bredblox, but what's in a name? This is just a nice little breadboard for electronic experiments. The Elenco Model 9830 measures 6-1/2" long x 2-1/8" wide x 5/16" thick with (2) power busses up both long edges and (63) double rows of more busses. The holes for components and jumper wires are approx .050" each and multiple boards can be interlocked via tabs and ports on the long edges. Now go invent something and get rich.

Because sometimes we (and presumably your pet fish) can get tired of all those boring earth tones. Our each is a pack of (20) small translucent acrylic pebbles suitable for, well, whatever pebbles are suited for, including aquariums, floral displays and craft projects. Approx 3/4” long in light blue, dark blue, or assorted candy colors.

Although they work best next to steel. You’ll get a whole bunch (that’s 25) of ceramic magnets at 3/4” dia and either 1/4” thick or 3/16” thick with a center bore approx 1/4”. (We’ll just grab what’s on top, OK?)

Our each is a pack of (10) common cathode 5mm dia red/green/blue LEDs. Clear lens, 20mA rated for 100K hour life. 3V supply will work for all. You also get 100 Ohm and 510 Ohm resistors to step down 5 and 12VDC respectively. Luminous intensity is 4,000 mcd.

Don’t blame us, it says that on the box. Measuring 9-1/2” x 4-1/2” dia, this canister-shaped amplified speaker system for your Bluetooth device has a pair of full-range speakers on one end and a sub-woofer on the other, which is why it’s the meanest speaker in the jungle. Internal rechargeable battery with mini-USB, rotary volume control, power switch, pause/play, next/prev song. No blueteeth? It accepts SD cards, external USB and an auxiliary input. Plays for 1-1/2 to 4 hours depending on volume, so listen to your mother and turn it down. Has a carrying strap, too.

You’ll get (10) pieces of clear acrylic medical grade tubing for your water fountains, Halloween displays or other hobby projects. Each measures 32” long x 5/32” OD x 1/8” ID. Made right here in the US of A.

These little PC-mount SPDT momentary switches from Omron® are rated for up to 0.1A at either 125VAC or 30VDC. Measures 3/4" x 1/4" x 1/4" with a 1-1/4" lever. UL/CSA.

The ball casters are great swivelers and quite snazzy looking, too. Seen on your better chairs everywhere. These are brass plated on 1-1/2" square mounting plates with 3/16" holes at the corners. You pick the 2" or 2-1/2" dia versions.

Treat yourself to an assortment of our finest negative meniscus lenses in sizes between 14mm and 52mm with focus lengths between -29.7mm and -169mm. Negative meniscus lenses spread light instead of concentrating it, so they're sort of de-magnifying glasses. (Perfect for reading if your vision is too good.) You get (4) lenses in each of (5) sizes for (20) total.

From the official Sharpie® people, this set has (20) fade-, water- and smear-resistant markers: (10) fine point in blue, green, yellow, neon yellow, tangerine, both neon and leg-warmer orange, hot pink, red and brown; plus (10) ultra-fine point markers in black, navy, techno and nano blue, aqua, green, orange and optic orange, magenta and jellie pink. They’re for coloring the 12-page aquatic-themed coloring book. (Be assured that when it’s all filled in you’re permitted to color non-ichthyological things indefinitely with the same markers.)

Ten electrical leads with an alligator clip on each end. Each lead is about 20" long, not counting the 'gators. Vinyl coated 20-22 ga. wire with a vinyl cover over each clip. They come in an assortment of five colors with two leads in each color. The manufacturer calls them heavy duty but we would restrict them to the light currents and low voltages you will be using in your home experiments. Our each is a set of (10).