STP 420ES Tissue Processor from Thermo Scientific

The Thermo Scientific STP 420ES Tissue Processor can improve laboratory's workflow efficiency with rapid conventional processing. This truly revolutionary instrument can accommodate overnight processing, same-day processing, or just about anything in between—with this dual chamber processor.

  • Reduce turn-around time and deliver results faster
  • Increase your flexibility with completely independent dual processing chambers
  • Reduce your laboratory's use of organic solvents and process Xylene-free with Fast Flex reagents
  • Achieve rapid processing without microwave technology or high temperatures



  • STP 420ES tissue processor features continuous movement of up to 360 cassettes within the main processing chamber
  • Rotational agitation, long used in other industries, provides a more efficient, dynamic means of tissue-fluid exchange and interaction
  • Recent studies conducted with a major Midwest university show fluid exchange ratio of the rotational agitation to be seven times more effective in processing tissue than conventional tidal agitation
  • To accommodate traditional tidal action, unit also has a 60-cassette processing chamber
  • Secondary chamber can be operated in conjunction with, or independent of, main chamber
  • Unit is completely enclosed and incorporates self-ventilation via a water tank and charcoal
  • Optional use of the Remote-fill-and-drain system minimizes reagent exposure risks, simplifies reagent changeover, and can be used during runs


  • Dual processing chambers
  • Dual rotary valves—separate and independent of each other
  • Independent programming for either chamber
  • Patented rotational agitation in the main chamber
  • Easy-to-use touchscreen operation with instant visualization of processing data and reagent status
  • Reagent management system
  • Fixed end-time programming
  • Reagent reduction carryover cycle
  • Four 5L paraffin reservoirs with quick-melt feature using multi-faceted cylindrical columns within the reservoirs
  • Ten 5L reagent vessels
  • Internal UPS system
  • Self-ventilation via a water tank and charcoal

Physical Specifications:

  • Dimensions (D x W x H): 25 x 25.2 x 59.2 in. (63.5 x 63.9 x 150.3cm)
  • Total Height including monitor: 59.2 in. (150.3cm)
  • Weight: 441 lb. (200kg)
  • Total Cassette Capacity: 420 (360-cassette capacity in rotational [main] chamber; 60-cassette capacity in secondary chamber)