We generate revenue from the production of parts sold to automotive and light-truck Original Equipment Manufacturers (“OEMs”), or Tier 1 suppliers at the direction of the OEM, under long-term supply agreements supporting new vehicle production. Such agreements also require related production of service parts subsequent to the initial vehicle production periods. Additionally, we generate revenue from the production of parts sold in aftermarket service channels and to non-automotive commercial customers.

We have no material contract assets as of September 29, 2019. Contract liability balances primarily include discounts recognized as a reduction in sales at the point of revenue recognition, but which will be applied by the customer agreement after the end of the reporting period. The activity related to contract liability balances during the three month period ended September 29, 2019 was as follows (thousands of dollars):

Balance, June 30, 2019	$	932
Discounts Recorded as a Reduction in Sales		495
Payments of Discounts to Customers		(915	)
Other		(6	)
Balance, September 29, 2019	$	506

Revenue by product group for the periods presented was as follows (thousands of dollars):

	Three Months Ended
	September 29, 2019		September 30, 2018
Keys & Locksets	$	32,469	$	34,352
Door Handles & Exterior Trim		31,391		25,958
Power Access		19,458		22,399
Latches		13,897		11,055
Aftermarket & OE Service		10,913		10,984
Driver Controls		9,785		10,747
Other		2,049		1,664
	$	119,962	$	117,159

Revenue by customer or customer group for the periods presented was as follows (thousands of dollars):

	Three Months Ended
	September 29, 2019		September 30, 2018
Fiat Chrysler Automobiles	$	25,482	$	30,297
General Motors Company		33,838		25,287
Ford Motor Company		15,812		15,523
Tier 1 Customers		17,747		17,816
Commercial and Other OEM Customers		21,346		20,928
Hyundai / Kia		5,737		7,308
	$	119,962	$	117,159