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Lawrence Engineering Service No. 250-BT

• Type: Closed Body Enhanced Mannheim
• Size: 10 Inches
• Material: Boxwood
• Scales:
  • Front: A [ B CI C ] D K
  • Rear: [ S L T ]
• HvH: 1574

With faux-leather paperboard case. Rule is used and paint is discolored. Plastic runner. Unlike the B-10 this one has trig scales. The reverse of the slide shows the number 711.

The interior of the body, under the slide, is marked "R H S No. 6". Considering the source of the rule (an estate sale in Seattle), it's likely that the rule was once part of Roosevelt High School's collection and didn't get returned at the end of the school year.

Rule kindly provided by Sara Teller.