Rolex Caliber 3035 VS. 3135 Watch Movement

What is the difference between Rolex caliber 3035 and 3135?

The Rolex caliber 3035 was introduced in 1977 as what many refer to as a high-beat caliber 1575. Ten years later, in 1988, they put out the caliber 3135 with a few upgrades. It is still used today. Any other differences? Please comment below.

	Rolex Caliber 3035	Rolex Caliber 3135
Orgin	Swiss made	Swiss made
In-House?	Yes	Yes
Year Introduced	1977	1988
Replaces Caliber	Rolex 1575	Rolex 3035
Jewels	27	31
Power Reserve	42 Hours	50 Hours
Beats Per Hour	28,800 vph	28,800 vph
Date?	Yes	Yes
Hacking?	Yes	Yes
Crown	Counterclockwise to set time	Clockwise to set time
Regulation	Microstella	Microstella
Balance Spring	Free sprung Breguet	Overcoil Breguet with Kif shock
Balance Cock Stud	Hairspring glued on	Hairspring laser welded on
COSC?	Yes and No	Yes
Models	Date, Datejust, Submariner, Sea-Dweller	Date, Datejust, Submariner, Sea-Dweller, DeepSea

Caliber Commentary:

Tools posted this in the Rolex Forum:

The 3035 is almost identical to the 3135 in size and basic composition…..
The 3135 movement picked up a full balance bridge, larger balance wheel and went from 27 to 31 jewels.. It’s basically just an evolution… Much like it will be when they all get fitted with the Parachrom hairspring and the Paraflex shock system…. Identical again, except for the new parts…

Padi56 on TRF makes an interesting note about the hairsprings: