Is my transformer enough for Hello?

My chime box has 2 wires, one connected to "front" and one connected to "trans". Per Nest, that should work just fine depending on the transformer. Well, I finally found the transformer and the only thing it says on it is "16 volts". Nest says I need 16-24 VAC, is that volts? Sorry, I'm not very electrically inclined. Does anyone who already installed a Nest Hello have input they can share on my setup? I've almost gone to home depot twice to buy one but I'm awaiting my pre-order for the Google Home Mini and I just want to make sure install will go smoothly.