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SMC Spider
(#1215, 2434)


Front View Rear View Side View
Front View Rear View Side View
Front View: Open for Rigging Rear View: Open for Rigging
Front View: Open for Rigging Rear View: Open for Rigging

Technical Details

I acquired my SMC Spider from On Rope 1 in 2009. I acquired another in 2017 as part of Bob Thrun’s collection.

My Spider is 214 mm. tall, 85 mm. wide, 41 mm. thick, and weighs 554 g.

The SMC Spider shares many of the features of typical lever box descenders, but it has the characteristic rope path of a bobbin, the lower bollard rotates, and it has a double stop feature, so it meets my criteria for calling it a double-stop bobbin. The body is pear-shaped with a clip-in eye at the base. The rope channel is milled into the device, and the white line in the picture probably illustrates it more clearly than I can describe. The rope channel is 15.2 mm. deep. Starting at the top left, the rope passes right of a small anvil with a V-shaped rope groove milled into it. An 8 mm. steel wear pin protects the anvil. The rope continues down and counter-clock-wise around a reverse-C-shaped lower bollard, then up along the right side, around another steel ear pin, and out at the top right side of the Spider. Two more wear pins protect the rope channel on the bottom and center right.

The lower bollard is milled from aluminum. It is pressed onto a 16 mm. axle that passes through a bronze bearing in the back plate and is fastened to the operating lever with a button-head hex cap screw. The front of the axle has a groove turned in it for the cover plate notch to clear. The lever has milled cutouts to reduce weight.

The front plate is hinged to a 5 mm. button-head hex cap screw fastened to the right side of the body. The plate is made from 1.6 mm. stainless steel, and has cutouts for the eye, a botch for the axle mentioned earlier, and an irregular cutout for a spring-loaded plunger that holds the plate closed.

The front of the Spider is marked with an anchor icon, "Spider," a rope with a stylized arachnid, the SMC logo, "Quality gear for life," a fist icon. The Reading-Is-Dangerous icon, "RopeØ11mm - 12mm," "MBS 12kN," "MEETS NFPA 1983 (2006 ED.)," "Rope Ø12.5mm," "MBS 13.5kN Light Use," "MLN 8880," the Underwriters Laboratories "CLASSIFIED" logo, and "20 JF." The inside has a printed anchor icon and a white line showing the rope path.


Do not confuse the SMC Spider with the Repetto Spider, an earlier bobbin of the same name.

Don't let the two different rope size instructions confuse you, just find a 12.5 mm. diameter rope with a diameter between 11 mm. and 12 mm, and use it.

Don't let the two different breaking strengths bother you either, just go on a diet if you are to heavy for either (i.e., if you weigh more than 2697 pounds).

Seriously, though, the SMC Spider is very well made, it just suffers from SMC’s exposure to U.S. lawyers. It has the two characteristic disadvantage of lever boxes: complex manufacturing increasing its expense, and an enclosed design that makes it suffer in heavy mud. The lever has a double-stop capability, but I do not like this type of feature for a variety of reasons. The Spider is also heavy, but it doesn't allow for the ropes used by the bigger-is-better crowd. It is probably not the best stop bobbin for normal cavers and climbers, let alone the best descender, but it is a nice descender nonetheless.

Instructions Instructions

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