Balboa Water Group EL2000 M3 and EL2001 M3 Replacement Board PN 53834-05 Balboa Water Group PN 53834-05 Replacement Circuit Board for EL2000 M3 Spa Pack PN 53834-05 is the current version of the main circuit board used in EL2000 Mach 3 and EL2001 Mach 3 spa packs.PN 53974-05 which is the EL2001 main board differes only in that Jumper W15 is moved to J98. Software version is 32. This board can also replace earlier versions of the 53834 or 53974 boards. Comes with 1 year warranty. We accept PayPal and Credit card (Visa or Mastercard). If you are ordering multiple units and part, please call us to see if we can save you shipping cost for multiple item orders. No taxes to US residence! Please allow 4-6 days for shipping via UPS Ground to USA or Canada. You will be emailed a tracking number to the email address you provide us. Expedited Shipping services are available! Thank you for shopping Cedar Tubs Direct your #1 Hot Tub Parts Replacement store!