I have never seen a mechanical pole pruner with a finger trigger. I have seen gas powered pruners built by Echo (I think) that have a pruner head activated by a trigger. I have never seen them used, so I would guess they are not worth the expense. The standard pole saws with a 10" blade are quite light and can cut small as well as larger (up to 6" or so) limbs very easily. Be sure to pick up an extra blade when you pick one out, dull blades on a pole saw are about as useful as flat tires on your truck. I purchased a pole saw head with replacable blade for about $20 from a large mower/saw shop. Then I got a 12' dowel rod from Home Depot, shaved the end to fit, and made a commercial-grade pole saw for $30. Replacement blades run about $9.