Better than the one in the kit I bought for 5.4 timing. The kit compressor was bent and weak in the box. Don't use a 10mm, you're just bending the crank of the tool by hand. If you need more than necessary, move the tool. The spring on the back of cylinder 5 is hard to see and the tool head is big, you can be a rabbit and catch the head, just change the position and everything should work fine.