Looks cool, but today it's $99 on Amazon. At least the one in the link is.

I now use the Silca Bluetooth pump to top off tires to correct pressure (as well as carry it instead of CO2 on training rides). It will even work on my HED Jet disc without a crack pipe.

I use this one which is well-suited to disc wheels right out of the box. Pricey? Yes, but it helps me keep my transition bag and transition setup sparse and it also makes traveling to races easier as this pump is very, very small.

Ok- I know this topic has come up many times, but like many of you my search for a great transition pump was never quite resolved, until now!
Electric pump with USB charging, 12.9 oz/366 g, 8 inches long, 2 1/4 inch dia, digital gauge, and auto shut off with selected pressure up to 120 psi. It even comes with a water bottle cage mount ! Price is about $ 49 on Amazon.
I tested this extensively before using at Oceanside and St George. Battery will last about 8-10 minutes of pumping, which is enough to fill from flat about 4 - 700c x 25 tires to 100 psi, or many top offs. It takes slightly under 2 minutes to fully inflate a flat tire (100 psi). It takes about 5-10 seconds to top off 5- 15 psi. I made multiple tests of the gauge, with my Topeak digital as the “standard. In all cases the Topeak measured within 1 psi (@ 100 psi) of the pumps gauge, with the Topeak always being the same or 1 psi lower. I attribute this difference to small pressure loss engaging and disengaging the gauges.
The auto shut off has worked perfectly every time. I have set my pump to 102 psi. The process is simple- 1) open presta valve 2) screw on schrader to presta adapter 3) attach pump head 4) press “on” button 5) wait a few seconds for pump to reach set pressure and turn itself off. DONE!
Important note- THIS PUMP WILL NOT WORK IF YOU USE TUBE STYLE PRESTA EXTENDERS. You have to use the supplied schrader to presta adapter, which screws directly on to the presta valve.

https://www.amazon.com/...tables/dp/B0798RZMHJ

Dozens of racers at Oceanside and St George asked where to get one as I was topping off my tires and several friends tires.
Super easy to stow in the supplied morning clothes bag, AND no pumping and struggling to read gauges in the dark (or without your readers!)

Take a look at the Fumpa I posted a link to. Perfect for race day. At road pressures I think it’s more accurate than the stated +/- 3%.

Does it work with discs without the crackpipe?

The pump head is very similar to a disk crackpipe, except it has a locking lever on top of the head. You would need enough space above the presta valve for this lever (which could be shortened), or have enough play in the valve to lean it forward.
On a side note- I honestly do not understand with all the data that is out there why anyone is still riding a disk in triathlon. There main benefit is in point to point high speed (30 + mph) time trials, and even then the benefit is only a few seconds over 40k in high yaw wind conditions :-) That is a whole other thread that would be highly entertaining!

My bad. Here it is and I’ll insert the link into my first post:

https://www.fumpapumps.com/shop/fumpa/

Cool, thanks. I guessed this is what it was based on your description. The Amazon generic ones are cheaper, but having the built in presta adapter sounds awfully nice. The head on this thing fits on disc wheels no trouble?

Ok- I know this topic has come up many times, but like many of you my search for a great transition pump was never quite resolved, until now!
Electric pump with USB charging, 12.9 oz/366 g, 8 inches long, 2 1/4 inch dia, digital gauge, and auto shut off with selected pressure up to 120 psi. It even comes with a water bottle cage mount ! Price is about $ 49 on Amazon.
I tested this extensively before using at Oceanside and St George. Battery will last about 8-10 minutes of pumping, which is enough to fill from flat about 4 - 700c x 25 tires to 100 psi, or many top offs. It takes slightly under 2 minutes to fully inflate a flat tire (100 psi). It takes about 5-10 seconds to top off 5- 15 psi. I made multiple tests of the gauge, with my Topeak digital as the “standard. In all cases the Topeak measured within 1 psi (@ 100 psi) of the pumps gauge, with the Topeak always being the same or 1 psi lower. I attribute this difference to small pressure loss engaging and disengaging the gauges.
The auto shut off has worked perfectly every time. I have set my pump to 102 psi. The process is simple- 1) open presta valve 2) screw on schrader to presta adapter 3) attach pump head 4) press “on” button 5) wait a few seconds for pump to reach set pressure and turn itself off. DONE!
Important note- THIS PUMP WILL NOT WORK IF YOU USE TUBE STYLE PRESTA EXTENDERS. You have to use the supplied schrader to presta adapter, which screws directly on to the presta valve.

https://www.amazon.com/...tables/dp/B0798RZMHJ

Dozens of racers at Oceanside and St George asked where to get one as I was topping off my tires and several friends tires.
Super easy to stow in the supplied morning clothes bag, AND no pumping and struggling to read gauges in the dark (or without your readers!)

Maybe I'm just getting old but I have never had any issue topping off my tires with a simple manual track pump. When I flat a CO2 cartridge always has done the trick. Now don't get me wrong, I love technology (I use ETap, power meters, cycling computers, etc.) but this just looks like a solution looking for a problem.

I don’t carry one either. I keep my floor pump in the car where I inflate my bike and then walk it into transition.

Cool, thanks. I guessed this is what it was based on your description. The Amazon generic ones are cheaper, but having the built in presta adapter sounds awfully nice. The head on this thing fits on disc wheels no trouble?