XTREME model is a garage door accessory device.
The warranty on the accessory is from XTREME.
The model is still available.
XTREME model accessory instructions and owners manual in PDF format at NO CHARGE!
VIEW / DOWNLOAD by clicking HERE
xtreme_425_1671_10ft_extension_kit_chain_om.pdf
(0.35 MB in English) This requires Acrobat 10 or higher