Absolute Gutters uses Raytek Hidden Hangers able to withstand 297 lbs. of pull pressure.

The Hangtite is self bracing at the points of greatest stress. Manufactured of heavy tempered aluminum, the channel-formed design makes it the strongest hanger of its type.

Excerpt from gutterworks.com:

In the absence of a standardized test in the gutter industry that could be used to evaluate the pull value of hangers, Raytec developed the test procedure demonstrated below.

The procedure consists of a set of gripper hooks attached to the outside edge of .032 Aluminum gutter. Standard hidden hangers were screwed into a 3/4" fascia board backed by 2" x 4" spruce, with a 1 1/2" hex head screw. A screw jack was used to pull the gripper hooks at an angle of 45% with an "S" type load cell measuring the lbs. of force exerted on the hanger. Displayed on a Total comp electronic digital indicator, each hanger was evaluated for the amount of sag it displayed at various weights and, finally, the point at which it broke.

Our tests are in no way intended for use other than comparing one hanger with another.

Twelve hangers of similar mounting configuration, commonly used in the gutter industry, were evaluated. The Raytec Hangtite™ proved superior to all of the hangers tested. Of the total tested, the Raytec hanger is priced at about the mean average of the group.

Findings:

At 119 lbs. pull, 4 of our competitors' hangers broke loose.
At 140 lbs. pull, 3 more of our competitors' hangers broke loose.
At 230 lbs. pull, 4 more of our competitors' hangers broke loose.
The Raytec Hangtite™ hidden hanger hold up to 297 lbs!

If you what to find out the strength of your hanger put it to the test like the pictured installer is doing, and you will find out that NO hanger holds up like the HANGTITE™ and HANGFAST™