Weight 125 grams

Does not harm seals

you can change the end caps out to the oversized torque caps

Durable and water resistant

Volume (Per Stroke): 90

JetBlack S1 Sport Magnetic Trainer with Lite App Envelope Shipping Weight 125 gramsThe JetBlack S1 Sport Trainer is a magnetic resistance bicycle trainer that is perfectly tuned for fitness riding The S1 is an economy package that has a fixed resistance mode When used with the full range of JetBlack sensors You'll be able to fine tune your entire training experience You can even upload your session to Training Peaks and Strava All JetBlack trainers come with a lifetime warranty. Out of the box, it only works with QR end caps.