These are 2 bagless Hoover upright vacuum cleaners. Hoover UH72400 is lighter, with lower profile, and features Steerable Technology that makes navigation smooth. While the Hoover UH72600 is more powerful, with wider cleaning path, longer power cord, and comes with more tools.
You can read the table below to get more similarities and difference between Hoover UH72600 and UH72400:
Compare Hoover 72400 and 72600
| Hoover UH72400 Air™ Steerable Bagless Upright | Hoover UH72600 WindTunnel® 3 High Performance Bagless Upright | |
|---|---|---|
 |  |
|
| Design | Upright | Upright |
| Steerable Technology | Yes Steerable Technology allows you to swivel and turn around by twisting the handle | No |
| Price | $159.99 at Hoover.com on July 20, 2014 | $179.99 at hoover.com on July 20, 2014 |
| Bagged or Bagless | Bagless | Bagless |
| Dirt Bin Capacity | 1.2 liters | not specified |
| Bottom-Release Dirt Cup | Yes | Yes |
| Power Source | Corded | Corded |
| Cord Length | 30 ft | 40 ft |
| Retractable Cord | No | No |
| Power | 11 Amps, 1300 Watts | 12 Amps, approximately 1440 watts |
| Motorized Brushroll | Yes | Yes |
| Brushroll On/Off | Yes | Yes |
| Height Adjustment Type | Automatic Adjustment | 7 Level Manual Adjustment |
| AllergenBlock | Yes blocks 99% of allergen particles from re-entering the air. | not specified |
| Washable Filter | Yes | Yes |
| HEPA Filter | Yes | Yes |
| Headlight | No | No |
| Weight | less than 14 lbs | weighs about 20 pounds |
| Cyclonic Action | Multi-Cyclonic | Multi-Cyclonic |
| WindTunnel Technology | WindTunnel® 3 Technolog | WindTunnel® 3 Technolog |
| Nozzle Width | 12.5" | 15" |
| Handle | Removable Handle | Fixed |
| Hose Type | stretch hose | stretch hose |
| Self-propelled | No | No |
| Edge Cleaning Brush | No | No |
| Performance Check Indicator | not specified | Yes |
| Included Tools | Crevice Tool, Dusting Brush | Extended Length Crevice Tool, Rotating Pet Power Brush, Rubberized Hair Lifter |
| Cleaning Wand | Yes | Yes |
| Hose Length | 12' | 12' |
| Color | Gray | Red |
| Warranty | 5 year limited warranty | 5 year limited warranty |
| Manual | download manual | download manual |
Overall, if you have thicker carpet or multi level carpets, the UH72600 suits to your needs better. If you have low pile carpets and need a vacuum that is easier to turn around furniture and corners, the UH72400 is for you.