The SK-8835/SK-884x family are a series of ThinkPad-style discrete keyboards marketed by IBM and Lenovo. Visually based on the keyboards for T30-era ThinkPads, these are produced by LITE-ON for IBM and Lenovo and feature a unique feeling scissor-switch not found on ThinkPad laptops of the era. They also do not utilise strain gauge-based TrackPoint pointing sticks, instead, they use the force-sensitive capacitor2-based Synaptics TouckStyk pointing sticks3. All USB variants of these keyboards sport a two-port USB hub on the rear of the keyboard, but all variants allow for cable stowage and routing on the bottom and have two-setting flip-out feet. The family was originally introduced as an IBM one, however, Lenovo-branded ones first appeared in 2005 after they purchased IBM's Personal Computing Division4. IBM continued to have models manufactured with their name for use with IBM server consoles until 2014 when Lenovo also purchased IBM's x86 Server Business5.
All members of the family are based on the style of contemporary ThinkPads when the first members were introduced in 2003, which were the IBM ThinkPads T30, T40 and their R-series derivatives. The cues that indicate this fact are the grey coloured F and navigation keys and rounded ThinkVantage button that both the preceding T20 and succeeding T60 lacked, and the roundness of the trackpad and trackpad buttons that has not been seen on ThinkPads since the T40 series. As such, all the SK-884x keyboards resemble a T30 or T40 missing the screen. The SK-8835 extends the design with the addition of a dedicated numeric keypad that has not been seen on a discrete ThinkPad-style keyboard since and was only later implemented on a ThinkPad laptop when the W700 was released in 20086.
The rear and aft of all the keyboards are unique for discrete ThinkPad-style keyboards as they feature two-setting flip-out feet, extremely flexible cable guttering, and a two-port USB hub (excluding SK-8840) that has not been seen on discrete TrackPoint keyboards since. Coupled with the fact this family are the only ThinkPad-style keyboards that also feature a trackpad (excluding SK-8845CR), these can be considered the most flexible and practical ThinkPad-style keyboards available for the desktop.
On the inside, these keyboards contain a ThinkPad-like keyboard assembly, a Synaptics TouchStyk pointing stick module, and a Synaptics TouchPad trackpad assembly (excluding SK-8845CR) that are hooked to a PS/2 (SK-8840) or USB controller (rest). The SK-8835 also features a separate numeric keypad assembly. As stamped on the inside of the case, the plastic used is ABS.
As mentioned earlier, the keyboard assemblies all members of the family use were unique to them are we not featured on period ThinkPads, although some have likened the key feel to be a stiffer Chicony OEM ThinkPad keyboard of the 2000s. The inclusion of a TouchStyk is also relatively unique in ThinkPad circles as only the later E-series laptops from Lenovo are presently known to use TouchStyks instead of TrackPoint IV8. Despite this, the performance of their pointing sticks is still adequate and serviceable.
The keyboards within the family took a variety of names over the years. Perhaps to reflect the fact these technically lacked a 'true' TrackPoint pointing stick, the names avoid mentioning "TrackPoint" directly and instead refer to these as "UltraNav" or "Integrated Pointing Stick" keyboards. Despite obviously being based on ThinkPad aesthetic design, most of the keyboards also do not refer to themselves as ThinkPad products until Lenovo took over the rights for making these for the home and office PC markets.
An exhaustive list of names in approximate chronological order include:
The Variants section illustrates what variants have what specific name.
The SK-8835 was the largest member of the family, uniquely featuring a dedicated numeric keypad that makes the keyboard effectively a full-size keyboard in the footprint of a tenkeyless keyboard. The SK-8835 were introduced in 200310 and most part numbers (constituting European, Middle Eastern and African locale versions) were officially withdrawn in September 200911. Lenovo also later referred to the keyboard as the Lenovo ThinkPad Full-Size UltraNav USB Keyboard12.
The SK-8840 was the only PS/2 member of the family, otherwise visually identical to SK-8845 except. Due to the PS/2 connectivity, this is the only member of the family that lacks the two-port USB hub the others have. It was introduced by March 2004 for the IBM 17" 1U Flat Panel Monitor Console13, seemingly confined for use with IBM's x86 Server Division and was out of production by 2014, thus Lenovo never put their name on the design. In March 2006, the price of the SK-8840 was $99.00 USD and its cable length was 3 metres14.
The SK-8845 was the short-cable USB version of SK-8840 released by April 2004 and intended for use with IBM desktop and ThinkPad laptops of the period16. IBM support documentation also referred to these early SK-8845s as the IBM USB Travel Keyboard Option, likely in reference to the keyboard being an option for IBM PCs such as the IBM IntelliStation M Pro17. Like the SK-8840, in March 2006, the price of the SK-8845 was $99.00 USD18.
The SK-8845RC is a variant of the SK-8845 with a longer (3-metre19) cable and is typically only intended for use with server consoles but is otherwise electronically identical. Introduced by 2010 under the original name IBM UltraNav USB Keyboard (40K5xxx), they seem to be originally utilised with IBM 1U 17-inch and 19-inch Flat Panel Console Kits intended for use with rack-mounted IBM System x and BladeCenter servers20, then made available with a new part number nomenclature (94Y6xxx) for the IBM System x as the IBM Keyboard with Integrated Pointing Device USB21.
The SK-8845CR is the youngest member of the family bearing the SK-884x shape but lacking a touchpad, thus making this the only non-UltraNav variant. Most examples bear the name of IBM Keyboard with Integrated Pointing Device USB like later SK-8845RCs in the context of use with the IBM/Lenovo 1U 18.5-inch Standard Media Console (part number nomenclature 46W67xx). Interestingly, Lenovo also designates a single part number of this keyboard (00MW310) as the Lenovo UltraNav Keyboard USB despite specifically noting "This keyboard does not include a trackpad/touchpad"23. It seems SK-8845CR was likely introduced in August 2013 with IBM also claiming the system's keyboards to be UltraNav keyboards24. By 2015, another part number (00WV000) was introduced for the IBM Storage Appliance 2421 Model AP125 and is likely the last IBM-branded ThinkPad-derived/style product introduced.