LIFTMASTER model 877LM keyless entry. It transmits using rolling code on frequency MyQ.
The warranty on the 877LM garage door keyless entry is 1 year from LIFTMASTER.
The model 877LM is still available.
LIFTMASTER model keyless entry instructions and owners manual in PDF format at NO CHARGE!
VIEW / DOWNLOAD by clicking HERE
liftmaster_877lm_om.pdf
(1.81 MB in English) This requires Acrobat 10 or higher