The sample of quasars observed in our HST program is drawn from a compilation of quasar pairs with g*<21mag (Hennawi+ 2006, J/ApJ/651/61 ; 2010, J/ApJ/719/1672 and Findlay+ 2018ApJS..236...44F), selected from the SDSS/BOSS footprints in the redshift range z~2.0-2.5. Our HST program includes 47 quasar pairs and four additional single quasars observed within the survey, leading to a total of 104 quasars (111 observations). Each quasar pair was observed with HST WFC3/UVIS-G280 grism for one orbit between 2016 September and 2017 March 12 (Cycle 23, program ID 14127, PI: Fumagalli).Optical spectra were obtained for a fraction of our quasar pairs from a variety of instruments and thus have different wavelength coverage and resolution. High S/N spectra were taken for 27 quasars using the Echellette Spectrograph and Imager (ESI) at the Keck II telescope and the moderate-resolution Magellan Echellette (MagE) optical spectrograph. Twelve quasars have medium- to low-resolution optical spectroscopy from several telescopes, such as the 6.5m Multiple Mirror Telescope (MMT), Calar Alto Observatory (CAHA), Keck, the 2.1m telescope at the Kitt Peak National Observatory (KPNO), and Gemini (see Table 1). (2 data files).