Yet some more code about this... the /g operation generates a list, below I assign all regex matches to a list called @types.

use warnings;
use strict;

my $_sensor_type =  'I2600*&^_A8699()^%#@C9800&*%A96';

my @types = $_sensor_type =~ /[a-z]+([0-9]+)/ig;

#parens aren't needed here but to make list clear,
#could have been:
#my @types = ($_sensor_type =~ /[a-z]+([0-9]+)/ig);

print join("\n",@types),"\n";
__END__
## prints ###
2600
8699
9800
96
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Another question that comes up all the time is about this $1 stuff and what a pain it is. So how to you avoid having to use $1? Use a list slice to assign $1 to a scalar without having to go via $1!

my $_sensor_type =  'I2600*&^_A8699()^%#@C9800&*%A96';
my $type = ($_sensor_type =~ /[a-z]+([0-9]+)/i)[0];
print "$type\n"; #prints 2600

#so what happens if the match and consequent slice fails?
$type ||= "some default";
#or check for undef
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There are lots of cases where this trick is handy. Some types of split scenarios can produce undef values and this special Perl operator ||= can override that to a value, like even "".