4-string · Bolt-on
STR SIERRA LS40, a 4-string bass. Passive four-string: two volumes and a tone, no preamp. The SIERRA series was relaunched in November 2018 after several trade-show prototypes, broadening the line to 4- and 5-string, passive and active, and LED-marker versions. Made in Japan by builders trained under Satoru Yatsuzuka. Ships with the STR semi-hard gig bag. STR describe the LS as their most standard model, built to a traditional detachable-neck specification with a deeply carved cutaway for unimpeded access to the top frets and a three- or five-piece neck for rigidity. The Aguilar Hot Jazz pickups use larger 6mm magnets and an over-wound design for a hotter output with heavy lows, while retaining playing dynamics. Blackwood is a technologically modified wood with the density and colour of ebony, made from natural material rather than plastic; both the maple and Blackwood boards carry abalone dot markers. Nut width 38.0mm, fingerboard radius 310R. SBB215 jumbo frets, bone nut, urethane finish. GOTOH 404BO bridge and GB707 tuners. Bolt-on construction is taken from STR's description of the LS line; the SIERRA spec sheet itself does not state it. Built by Deviser in Matsumoto, Nagano, Japan. No list price is published for this model.
| Construction | Bolt-on |
| Strings | 4 |
| Body | Ash |
| Neck | Maple, 3-piece |
| Fingerboard | Maple or Blackwood |
| Neck Pickup | Aguilar AG4J-HOT |
| Bridge Pickup | Aguilar AG4J-HOT |
| Controls | 2 volume, 1 tone (passive) |
| Bridge | GOTOH / 404BO |
| Made In | Japan |