Enjoy! #FF-This hashtag mostly shows up on Fridays, which should give you a good indication of what one of the Fs means. The other stands for Follow, and the two combine to make the phrase Follow Friday.. Follow Friday is essentially a Twitter holiday with the aim of getting people to follow one another.
Technical. Original manufacturers part,390 Mhz frequency, 9-volt battery operated, part number 976LM a 977LM keypad is substituted per the manufacturers change, Color: Grey Works with all Liftmaster, Sears and Chamberlain garage door openers, utilizing the 390 Mhz frequency.echnical. Original manufacturers part,390 Mhz frequency, 9-volt battery operated, part number 976LM a 977LM keypad is substituted per the manufacturers change, Color: Grey Works with all Liftmaster, Sears and Chamberlain garage door openers, utilizing the 390 Mhz frequency.
The Invisa HTR-7000s combine a 7â³ woofer and a folded-ribbon tweeter in a package that handles up to 250 watts of power with 90 dB/W/m sensitivity and 8-ohm impedance. Frequency response is specâd from 25 Hz to 35 kHz, and it requires a 9â³ cutout for in-ceiling installations.