Also check out the newest version of the Edge that has turn-by-turn directions, maps, and a color screen:
Edge 705 with HR, Cadence, & Map Data Card
Edge 705 with HR, Cadence
Edge 705 with HR
Features:

• Heart rate monitor and speed/cadence sensor
• Automatically records up to 1000 laps. Download to your PC
• Look up and navigate to stored locations
• Virtual Partner lets you "race" a virtual competitor, making training fun
• Heart rate monitor or speed/cadence sensor
• High-sensitivity GPS receiver

Editorial Review
Whether you're prepping for your next century ride or want a more accurate way to measure your performance on the trails, take your training to the edge with the Garmin Edge 305 GPS-enabled Personal Trainer and Cycle Computer. Bundled with everything you need, including a heart-rate monitor and a bike-mounted, wireless speed/cadence sensor, the Edge 305 is easy to use, requires no calibration, and features customizable screens and data fields to meet your needs. Measuring speed, cadence, heart rate, distance, time, calories burned, altitude, climb, descent, and more, the Edge 305 will help you to always know where you are and how far you've gone.

With a built-in barometric altimeter and heart-rate monitor, the Edge 305 goes a step beyond its little brother--the Edge 205. The altimeter delivers extremely accurate elevation readings, while a chest-strap monitor sends your heart-rate data to the 305 via a robust wireless transmission. In addition, this version of the 305 is bundled with the Garmin Speed/Cadence Sensor. This self-calibrating wireless sensor uses the same reliable technology as the heart-rate transmitter and attaches to your bike's rear chain stay, delivering speed and pace data while you train.

The Edge 305 couldn't be easier to use. Simply take it out of the box, install the speed/cadence sensor, snap the main unit into the included bike mount, and hit the road. The high-sensitivity SiRFStarIII GPS receiver maintains your position in tree cover and canyons, making the Edge 305 an extremely reliable navigation device. And with the customizable cycle computer, you can select from up to eight different data fields for continuous feedback. Garmin goes well beyond typical cycle computers by integrating GPS technology for basic navigation. In addition, the Edge 305 gives you the ability to overlay your ride data onto a course map and even "race" a virtual partner, making your training fun while helping to push you toward your goals.

The included, PC-based Training Center software gives you the tools to create workouts, manage and download courses, and create a detailed post-ride analysis that charts your performance. It also measures your speed, distance, climb, descent, and heart-rate data against varying terrain, elevation, and more. And with the Edge 305's built-in USB interface, it is quick and easy to upload and download information.

The virtual partner screen depicts a digital cyclist (representing your desired speed) in relation to your real-time speed. From this set of data the icons will show how far ahead or behind you are from your digital competitor. The Courses feature allows you to race against a recorded course to try and match previously set speeds at every point along the way.

Training in urban areas can be tricky, and undesirable traffic can skew training data. To help remedy this problem, Garmin has included an auto-pause function that pauses the training timer when you slow down below a specified speed and resumes when you speed up again so you can focus on your ride, not on your data collection. And with the auto lap function, this smart little device automatically triggers a lap every time you pass a specified location or travel a preset distance.

With its sleek, waterproof design (the Edge 305 meets IEC 60529 IPX7 standards, which means that its components can be submerged in one meter of water for 30 minutes), the 305 is the perfect companion on any bike, and it attaches to either the stem or handlebars. This lightweight device (88 grams) is powered by an 800mAh rechargeable lithium-ion battery and delivers an average of 12 hours of use per charge. The rugged case frames an easy-to-read, large, backlit display that makes it a breeze to view the data fields. So whether you're racing against your virtual partner, fighting to shave precious seconds off your old record, or training for the next big race, the Edge 305 will help you monitor your progress and make you a better cyclist.

What's in the Box
Edge 305 with heart-rate monitor, speed/cadence sensor, bike mount, Training Center CD, A/C charger, USB PC interface cable, quick reference guide, and owner's manual.

Product Description
Top of the line garmin Edge 305 GPS Bicycle Computer with Sirf Star chip. Take your ride to the next level with the Edge 305 - Garmin's GPS-enabled, personal trainer and cycle computer. From competitive road racing to mountain biking, the cyclist-friendly, lightweight Edge will help you achieve your personal best. With the easy-to-use Edge 305 on your bike, you'll always know where you're going and how far you've gone. For advanced cyclists, the Edge 305HRCAD comes packaged with BOTH a heart rate monitor and wireless speed/pedaling cadence sensor to provide valuable feedback. In addition, the Edge 305 incorporates a barometric altimeter for extremely accurate elevation and vertical profile data. Recreational cyclists looking for the perfect touring companion and fitness partner will love the Edge 305. The Edge 305 heart rate monitor lets you see whether you are training too hard or not enough. The heart rate monitor uses a robust wireless technology that eliminates cross-talk and interference and sends heart rate data to the Edge via a soft, comfortable chest strap. This data is stored with each track point for post-workout analysis. With its waterproof, sleek design, the Edge is the perfect companion on any bike, and attaches to either the stem or handlebars. Its rugged case frames an easy-to-read, large, backlit display that can show up to eight different data fields along with altitude and a map view.