This Manfrotto Mini Hydrostatic 5" Arm #8141 is a pint-sized arm that happens to be quite useful. It can support loads of up 7.7lbs. It is perfect for videographers, to mount a small external monitor or microphone to a video camera. The arm also features dual mounts to affix devices with 1/4"-20 & 3/8" threads.
The shorter arm (5") is also the more powerful. The pivoting pin is threaded with 1/4-20" and 3/8" studs so it can be attached to the top of a video camera to support a small monitor or other video accessory with an exceptional load of 7.7 lbs (3.5 kg).