Tuber (Tubular belay device)
| Tuber | |
|---|---|
 | |
| Other names | Tubular belay device, ATC, Reverso, Guide |
| Use(s) | Belay, Rescue techniques, ascending (atypical) |
| Pros | Well-tested and optimized, super-easy to give slack, useful for belaying of the second climber (guide mode), lightweight, can be used with double/twin ropes, multi-purpose |
| Cons | Does not provide assisted braking function, can bite into skin of the brake hand index finger if used inappropriately, in majority of the devices the setup for lowering of a second climber is cumbersome |
Tubular belay devices are the most commonly used belay devices during training of advanced climbing and rescue techniques, multipitching and management of twin/double ropes. In some countries/clubs, they have been replaced by assisted tubular belay devices for single-pitch training. They are prohibited in some gyms due to alleged security concerns (for details, see the security concerns section).
Belaying risks
Always hold/control the break strand at least with one hand and keep the break strand downwards unless giving or taking the slack. Keep your hand at least a few centimeters from the belay device to avoid pinching of the skin. Do not lift your hand too high (above the device) while giving the slack. One of the commonly seen bad habit is keeping the hand raised for a prolonged time during belaying.
Always hold the break strand downwards unless feeding/taking the rope 
Feed or take the rope from the front of the device 
Not holding the break strand can result in fatal injuries 
Holding the break hand too close leads to belayer risk of pinching the skin of the index finger. 
Do not lift the break hand unnecessary high during the break strand manipulation. 
Do not leave the hand in the upper position if not taking or giving the slack.
Belaying from the harness
Slack taking
Start in the resting position 
Feed the slack through the device by simultaneously moving both hands 
Move the belay hand back into a fully blocking position 
Tunnel up the rope by the belay hand to the resting position 
Final resting state, repeat the steps if you need to take more slack
Slack feeding
Tunnel down 
Feed the slack through the device by simultaneously moving both hands 
Put the belay hand back into the safe resting position 
Final resting state, repeat the steps if you need to give more slack
Belaying from harness at the anchor
During belay from harness at the anchor point it is important to redirect the rope through the anchor till the first two pieces of the running protection are placed. Otherwise if the climber would fall, belayer would be pushed downwards and at the same time the tuber would not block as both the break strand and the live strand would be pointed the same direction.