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Surly ExtraTerrestrial 27.5 Inch Adventure Tire Surly ExtraTerrestrial 27.5 Inch Adventure Tire
Surly ExtraTerrestrial 27.5 Inch Adventure Tire 27.5 x 2.5 - Black
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Surly ExtraTerrestrial 27.5 Inch Adventure Tire Surly ExtraTerrestrial 27.5 Inch Adventure Tire
Surly ExtraTerrestrial 27.5 Inch Adventure Tire 27.5 x 2.5 - Black

ExtraTerrestrial 27.5 Inch Adventure Tire

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  (1 customer reviews)
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Ride without limits with high volume, kick-ass adventure tires

When you're out on a ride the last thing you want is to be held back by your tires in any way.

Surly's ExtraTerrestrial Tires were designed to let you ride without limits by simply following the only tenets the brands has for tire design: they're high volume and they kick ass.

The ExtraTerrestrial tire was meant to serve as a heavy-duty off-road touring tire that shines on hardpack surfaces. It uses a nylon breaker in the sidewalls for cut protection, a molded pattern for anti-cut propagation, and a Kevlar cap under the tread to protect against flats.

The ET Tire uses a distinctly directional tread pattern and its width yields more traction than you might expect from a tire with such little rolling resistance. The tread is low profile with a file tread in between tread blocks.

The ExtraTerrestrial tire has enough width and traction for the soft stuff and won't bog you down on smooth or hard surfaces.

The finishing touch is a slate sidewall that brings an understated element of flair to any frame or kit.


  • Measures 27.5x2.5"
  • 60 TPI casing
  • Tubeless ready

B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.

The product weight specified is an approximate weight based on the manufacturer's specifications (if available) or our measurement of one or two examples. For most products, the weight will typically vary by 5% to 10%.


Weight: 990 grams


Wheel Size: 650B (ISO 584) 


Tire Width: 64mm (2.5in) 


Tire Type: Tubeless Ready 


Threads Per Inch: 60 

27.5 x 2.5 - Slate Grey

Mfg PartNum: TR7506 

27.5 x 2.5 - Black

Mfg PartNum: TR7505 

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Good tire, mounts easily
by Anonymous

No problems with setup. Tire is sturdy and rolls well, looks good too. Nice for commuting and groomed trail riding.

Reviewed 2/25/2021
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