Exhibit 10.6 ADDENDUM TO LEASE BETWEEN BJB ASSOCIATES, LANDLORD and INTELLIGENT CONTROLS, INC., TENANT DATED JUNE 21,1994 The lease is hereby revised as follows. All other terms and conditions to remain the same. 1. Lease to expire October 14, 2000 2. Space leased to total 14,520 square feet 3. Monthly lease payments to be as follows: May 1 through August 14, 1998 $4,970.00* August 15, 1998 - August 14, 1999 $5,272.50 August 15, 1999 - August 14, 2000 $5,580.72 August 15 - October 14, 2000 $5,908.41 4. There are no further options to renew 5. Tenant's share of real estate taxes and insurance is 88% * April 15 - May 14, 1998 Prorated as follows: 4/15 - 4/30 $4,580/30 = 152.67 Diem x 16 days = $2,442.72 5/1 - 5/14 $4,970/30 = 165.66 Diem x 14 days = $2,319.24 TOTAL DUE APRIL 15, 1998 $4,761.96 LANDLORD: BJB ASSOCIATES: /s/ Leilani McCabe By: /s/ Glenn Joziatis Witness Its Partner April 28, 1998 DATE TENANT: INTELLIGENT CONTROLS, INC. /s/ Sharon Binette By: /s/ Alan Lukas Witness Its President April 17, 1998 DATE BJB Properties 158 Greeley Street Hudson, N.H. 03051 April 3, 1998 INCON P.O. Box 638 Saco, ME 04072 ATTN: Mr. Stephen Leuth, PLANT MANAGER Dear Mr. Leuth: Enclosed are two (2) copies of Addendum to BJB ASSOCIATES-INTELLIGENT CONTROLS LEASE dated 6/21/94. Kindly sign and date both copies and return to us. Upon receipt, we will send you a fully executed copy. To confirm our discussion, the Lease Agreement Rider is amended as follows: Effective May 1, 1998, Landlord is to compensate Tenant $191.47 monthly for Landlord's share of utility costs for reduced square footage retained by Landlord. AGREED TO: /s/ Alan Lukas April 17, 1998 INCON DATE Kindly sign above, retain one copy and return signed copy to us. If you have any questions, please call Glenn Joziatis at 603-882-2638. Sincerely, BJB PROPERTIES /s/ Lonnie McCabe Lonnie McCabe LM/reg