Sealing system: Mechanical Seal MS or Sealless SL
Mechanical Seal = MS Usage: Pump tubes with MS are recommended for crystallizing, hardening and solid containing liquids. | Sealless = SL Usage: In all other cases you should give preference to sealless design because a sealless pump cannot fail by running dry. |

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...not be allowed to run dry! | ...can briefly run dry! |
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