Four Pictures, One Word, 500 Passenger Rewards Points!

If you've played 'Four Pictures, One Word' you know how frustrating it can be. Here's one I struggled with for a few hours. Can you figure it out?

Enter the correct answer below, and you'll score 500 Cars 108 Passenger Rewards points.

'Four Pictures, One Word' is a popular online game for Android and ios devices. The object is to determine one word that all four pictures have in common. Users are presented with a pool of letters from which to choose, and earn coins for each puzzle correctly solved. There are also options to eliminate letters from the pool, and place one correct letter in the answer. Those options cost the user coins.