Our VP for Sensing Fluid Pressure called this sensor from Kavlico “sweet.” Needs a 5VDC 20mW power source, and will likely put out 0-4VDC, contingent on pressure, from 0-5"/H2O max, we’d say. Measures 1-5/16" x 17/32" on a pair of 7/8" long 5/32" slotted mounting wings. The upper 3/16" OD barb is the low side, and the lower is (ironically) high. Has a 3-pin connector with legend on the back for power and output. Call for a data sheet.

It's a nonpolarized bimetal heat sensor, 1/2" long with rubber sleeves and 6" long leads. It's also mysterious, because when used as a thermocouple multimeter input, it reads approx 94° in nearly boiling water but approx 170° in ambient air. Wethinks some sort of inversion or scaling is going on, but a person with your smarts will surely figure it out.

This 4" x 3-3/4" x 1-3/4" medical take-out air sensor has (3) ports coming off the main 3-1/8" x 3/4" ID chamber, (2) leading to one sensor and the other leading to a second one, then through circuitry on a mounted PC  board leading to a 10-pin output connector. Also has a PCB-mounted 3V coin cell battery. The sensors have input, output and trigger voltage and a voltage output, but we have no specs. Nice parts and pieces, though.

Made to be used on the suction side of a vibratory pump, this flow sensor prevents measuring errors during water-flow pulses. Unit measures 2" dia (3" long with connectors) x 1-9/16". Uses 4.5-24VDC @ 5-13mA. Tubing connects via 1/4" OD hose nipples. Does not supply an output voltage but switches the signal terminal from ground to open. We'll throw in a data sheet for you, too. Digmesa part #974-9501.

How many what? Well, whatevers, as long as you can count them, which you’ll be able to do with this 24VDC, 1.7W, 6-digit, pulse-activated, non-reset counter. In a 7/8” x 1” x 2-3/8” clear acrylic case with a mounting arm and a quick-disconnect terminal on 4” leads.