Hotronic has provided backwards compatibility in the new components to protect investment and enable you to benefit from the longer life and improved charging systems. Your current Hotronic elements can be used with the new batteries and chargers.
| Compatibility |
| Component | Compatible With |
| All Insoles (Old and New) | Work with all (PowerPlus and prior) batteries |
| Pre-PowerPlus Batteries | Pre-PowerPlus, Power Plus 2.5 and 2.7 and Power Plus Chargers |
| 2.5 and 2.7 Batteries | Charge only with the 2.5 or 2.7 Power Plus (red plug) or Power Plus chargers |
| 3.5 Batteries | Charge only with the 3.5 Power Plus (blue plug) charger |
| Pre-Power Plus Charger | Use only with the Pre-Power Plus batteries |
| 2.5 and 2.7 Power Plus (red plug) and Power Plus Chargers | Use with the pre-Power Plus, Power Plus and 2.5 or 2.7 Power Plus batteries |
| 3.5 Power Plus Charger (blue plug) | Use ONLY with the 3.5 Power Plus batteries |
So, to upgrade and take advantage of the longer battery life and better charging, you need to purchase new batteries and chargers. To do this, see the item below.
If you are buying replacement items, unless you have usable batteries and charger that you are trying to match, it is recommended that you upgrade to the 3.5 units which have significantly more heating time and power.
