This is a refillable, pressurized air duster, used for cleaning computers and other electronics. It can be refilled using a standard bike pump, by attaching the pump to the valve at the back of the can.
This is more efficient and less wasteful than the conventional disposable air dusters. According Adam Fields, who tested the product:
I use this in my home office, and it works well. It’s a refillable pressurized air duster. While it doesn’t provide quite as much pressure, or last as long as a commercial Dust-off can, it is refillable using a standard bicycle pump, so there’s no danger of running out and it’s better for the environment. The product description says it requires their expensive compressor to refill, but that’s not true — you can use a bike pump to recharge it by connecting to its standard bike tire valve. (It explicitly says on the can you can use a bike pump.)
It’s available here.