We are here to help you For quick and easy service, contact us:   Phone:   630-761-1106 Fax:   630-761-1107 Toll Free:   888-744-6277		PC 1300 When does the battery need exchanging?  Which batteries does the SIGMA SPORT Pulse computer need?  Who can carry out the battery exchange?  How do I exchange the battery in the chest belt?  Where do I wear the watch?  How do I put the chest belt on?  Where should I position the chest belt?  Do SIGMA SPORT pulse computers switch off completely?  Can SIGMA SPORT pulse monitors be used by people who have been fitted with a pacemaker?   What could the causes be in the event that the pulse computer does not display the heart rate?   What is the reason for the pulse watch display becoming weak?  Why does the display sometimes turn black?  Are SIGMA SPORT pulse computers watertight and can they be used for swimming?   How long is the guarantee period?  Do SIGMA SPORT pulse computers interfere with one another?  Is there a longer or shorter elastic belt for the transmitter?   How long is the warranty?  What is the warranty coverage on SIGMA products? The warranty on SIGMA products in North America is 2 years from the date of purchase. The warranty covers defects in material and workmanship. The warranty does not cover batteries, wear-and-tear, wear caused by commercial usage, or damage caused by a crash/accident. Proof of purchase is required. If your SIGMA product is not functioning properly and you feel that you have a potential warranty claim, please contact SIGMA USA at 888-744-6277 for technical support and/or to receive a return authorization number. Operating instructions International