Front	Rear	Top
Left	Right	Bottom

Technical Details

I acquired one of these marked "KTD" from Ben Corby in 2021 and a second marked "JTF" from Equipment Outdoors in 2023.

These are forged from aluminum alloy and then clear anodized. Mine are 54 mm. long, 47 mm. wide, 79 mm. high, and weigh 52 g. The slots are 34 mm. long and 15 mm. wide. The top of the Omega oval carabiner that I use for comparing belay tubes sits 8 mm. below the ends of the slots. These have solid rod keepers.

One side is marked with the "Ø8.5-11mm," "KTD" or "JTF" respectively, and the "reading is dangerous" icon.

Comments

The following closely-related belay tubes include the unknown belay tubes as an example:

Image Device Keeper High-end Notch Anpen Cable U Brasovia Lightweight Cable U Climb Axe Max Cable U Climb X, Version A Cable U Clog Flyer, Version A Rod V Clog Flyer, Version B Rod V	Image Device Keeper High-end Notch Ellis Brigham Climb Rod V GrandWall Cable U I Climb (元鴻興有限公司) #652 Cable U Kailas Cable U Kong Chuy #940 Cable U Mad Rock Max Air Cable U	Image Device Keeper High-end Notch Ocùn Tuber, Version A Cable U Ocùn Tuber, Version B Cable U Rock Empire Guard Cable U Unknown Rod V Simond Tubik Cable U

Each of these is 55±1 mm. long and 47±1 mm. wide, and has a weight in the 54±3 g. range. Their slots are all 35±1 mm. long and 16 mm. wide. The main differences are that most have cable keepers and U-shaped notches on both ends, but some have rod keepers and V-shaped notches on the high end.

These have several distinctive features, but overall, perform like most devices of this type. The rope slots are hour-glass shaped, but this does not appear to affect their performance. They are slightly asymmetrical with a high and a low end, giving two distinct riggings. One would expect a difference in friction for the two riggings, with more friction if the braking line runs over the shorter end; however, I do not notice much difference.

Most of these have shallow U-notches at both ends. The Clog Flyer, Ellis Brigham Climb and Unknown have V-notches at the high end, so I call these notched belay tubes. The V-notches are not as tall and acute as those on the Trango Jaws and its equivalents, so they do not provide as much braking. The U-notches on the others are are too shallow to noticeably amplify braking.

I prefer the ones with the rigid rod keeper. For the others, the plastic-coated cable keeper is moderately flexible, but stiff enough that it tends to stay out from under the rope.